Lowell Corporation Mechanical Ratchet Clutches, Model 75

Rugged and reliable for heavy-duty applications
Lowell ratchet clutches are designed from standard bodies, gears, pawls, and springs. Forces are applied in an optimum manner between the solid steel gear and hefty pawl so that loads are in compression rather than in shear. Gears are a low-carbon steel. Rugged tooth design as large contact area with pawl.

  • Mounting holes provided in body
  • Keyways are per ANSI/ASME B17.1
  • Lubrication is recommended after every 1200 hours of operation
  • Specials may be ordered with size, shape, and tooth arrangements of your choice
  • Fully locked neutral position
  • Free running neutral position available on request
  • Durable, cast iron construction
  • Custom models available
  • 100% made in USA
ImageOpeningPart NumberGear TeethMax TorqueOverrunning SpeedMaterialABCDEFGHJMeasurement Systemhf:att:pa_socket-openinghf:att:pa_gear-teethhf:att:pa_max-torquehf:att:pa_overrunning-speedhf:att:pa_materialhf:att:pa_ahf:att:pa_bhf:att:pa_chf:att:pa_dhf:att:pa_ehf:att:pa_fhf:att:pa_ghf:att:pa_hhf:att:pa_jhf:att:pa_measurement-system
Model 75 Ratchet Clutch - Square Gear Opening
1-1/16" Sq75901-95217241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-1-16-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
1-1/8" Sq75901-95218241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-1-8-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
1-1/4" Sq75901-95220241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-1-4-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
1-3/8" Sq75901-95222241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-3-8-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
1-1/2" Sq75901-95224241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-1-2-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
1-5/8" Sq75901-95226241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-5-8-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
1-3/4" Sq75901-95228241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-3-4-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
1-13/16" Sq75901-95229241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-13-16-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
1-7/8" Sq75901-95230241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-7-8-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
2" Sq75901-95232241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard2-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Square Gear Opening
27 mm Sq75901-M5227241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric27-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Square Gear Opening
28 mm Sq75901-M5228241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric28-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Square Gear Opening
32 mm Sq75901-M5232241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric32-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Square Gear Opening
34 mm Sq75901-M5234241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric34-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Square Gear Opening
38 mm Sq75901-M5238241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric38-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Square Gear Opening
41 mm Sq75901-M5241241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric41-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Square Gear Opening
42 mm Sq75901-M5242241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric42-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Square Gear Opening
46 mm Sq75901-M5246241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric46-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Square Gear Opening
47 mm Sq75901-M5247241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric47-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Square Gear Opening
50 mm Sq75901-M5250241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric50-mm-sq241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
1-1/4" Hex75901-95320241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-1-4-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
1-7/16" Hex75901-95323241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-7-16-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
1-1/2" Hex75901-95324241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-1-2-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
1-5/8" Hex75901-95326241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-5-8-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
1-11/16" Hex75901-95327241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-11-16-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
1-13/16" Hex75901-95329241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-13-16-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
1-7/8" Hex75901-95330241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-7-8-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
2" Hex75901-95332241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard2-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
2-1/8" Hex75901-95334241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard2-1-8-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
2-3/16" Hex75901-95335241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard2-3-16-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
2-1/4" Hex75901-95336241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard2-1-4-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
2-3/8" Hex75901-95338241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard2-3-8-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Hex Gear Opening
32 mm Hex75901-M5332241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric32-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
36 mm Hex75901-M5336241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric36-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
38 mm Hex75901-M5338241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric38-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
41 mm Hex75901-M5341241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric41-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
42 mm Hex75901-M5342241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric42-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
46 mm Hex75901-M5346241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric46-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
47 mm Hex75901-M5347241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric47-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
50 mm Hex75901-M5350241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric50-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
55 mm Hex75901-M5355241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric55-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Hex Gear Opening
60 mm Hex75901-M5360241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric60-mm-hex241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Bore Gear Opening
1-1/4" Bore75901-95120241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-1-4-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Bore Gear Opening
1-3/8" Bore75901-95122241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-3-8-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Bore Gear Opening
1-1/2" Bore75901-95124241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-1-2-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Bore Gear Opening
1-3/4" Bore75901-95128241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-3-4-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Bore Gear Opening
1-7/8" Bore75901-95130241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard1-7-8-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Bore Gear Opening
2" Bore75901-95132241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard2-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Bore Gear Opening
2-1/4" Bore75901-95136241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Standard2-1-4-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32standard
Model 75 Ratchet Clutch - Bore Gear Opening
32 mm Bore75901-M5132241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric32-mm-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Bore Gear Opening
34 mm Bore75901-M5143241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric34-mm-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Bore Gear Opening
38 mm Bore75901-M5138241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric38-mm-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Bore Gear Opening
42 mm Bore75901-M5142241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric42-mm-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Bore Gear Opening
47 mm Bore75901-M5147241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric47-mm-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Bore Gear Opening
50 mm Bore75901-M5150241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric50-mm-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric
Model 75 Ratchet Clutch - Bore Gear Opening
60 mm Bore75901-M5160241500 lb-ft60 rpmCast Iron, Steel6-1/2"5"1-9/16"4"1-7/8"5-1/4"1-7/8"3-3/4"17/32"Metric60-mm-bore241500-lb-ft60-rpmcast-iron steel6-1-251-9-1641-7-85-1-41-7-83-3-417-32metric