Operating with less backlash (play) than Precision Acme Lead Screws and Nuts, these provide increased nut life and more reliable movement in automated systems. Also known as single-start and self-locking lead screws and nuts, they have a single thread that runs the length of the screw. The nut travels only when the screw turns, so your system won’t unexpectedly move when the lead screw is at rest. All components are corrosion resistant for use in harsh environments. To ensure compatibility, select components that have the same thread type and thread size.

Travel distance per turn, also known as screw lead, is the distance a nut moves with one revolution of the lead screw.

3D CAD models availableFor technical drawings and 3-D models, click on a part number.

Lead Screws—Right-Hand Threaded

Thread Size Lg. No. of

Thread Starts Thread Type Speed

Ratio Travel Distance

per Turn Accuracy for Travel

Distance per Turn Hardness Tensile

Strength, psi Each

303 Stainless Steel

1/8"-20.8 6" 1 Rounded Acme 1:1 0.048" ±0.0006" per in. Brinell 160 90,000 6350K686 $21.56

1/8"-20.8 1 ft. 1 Rounded Acme 1:1 0.048" ±0.0006" per in. Brinell 160 90,000 6350K688 43.11

1/8"-41.7 6" 1 Rounded Acme 1:1 0.024" ±0.0006" per in. Brinell 160 90,000 6350K685 21.56

1/8"-41.7 1 ft. 1 Rounded Acme 1:1 0.024" ±0.0006" per in. Brinell 160 90,000 6350K687 43.11

9/64"-20.8 1 ft. 1 Rounded Acme 1:1 0.048" ±0.0006" per in. Brinell 160 90,000 6350K691 43.11

9/64"-20.8 18" 1 Rounded Acme 1:1 0.048" ±0.0006" per in. Brinell 160 90,000 6642K12 58.78

9/64"-41.7 6" 1 Rounded Acme 1:1 0.024" ±0.0006" per in. Brinell 160 90,000 6350K689 21.56

9/64"-41.7 18" 1 Rounded Acme 1:1 0.024" ±0.0006" per in. Brinell 160 90,000 6642K11 58.78

7/32"-20.8 9" 1 Rounded Acme 1:1 0.048" ±0.0006" per in. Brinell 160 90,000 6350K692 32.34

7/32"-20.8 18" 1 Rounded Acme 1:1 0.048" ±0.0006" per in. Brinell 160 90,000 6642K14 58.78

1/4"-20 1 ft. 1 Rounded Acme 1:1 0.05" ±0.0006" per in. Brinell 160 90,000 6350K696 50.68

1/4"-20 3 ft. 1 Rounded Acme 1:1 0.05" ±0.0006" per in. Brinell 160 90,000 6350K697 152.06

1/4"-20 6 ft. 1 Rounded Acme 1:1 0.05" ±0.0006" per in. Brinell 160 90,000 6350K133 176.00

1/4"-40 1 ft. 1 Rounded Acme 1:1 0.025" ±0.0006" per in. Brinell 160 90,000 6350K694 50.68

1/4"-40 3 ft. 1 Rounded Acme 1:1 0.025" ±0.0006" per in. Brinell 160 90,000 6350K695 152.06

3/8"-10 3 ft. 1 Rounded Acme 1:1 0.1" ±0.0006" per in. Brinell 160 90,000 6350K704 157.70

3/8"-10 6 ft. 1 Rounded Acme 1:1 0.1" ±0.0006" per in. Brinell 160 90,000 6350K705 186.56

3/8"-20 3 ft. 1 Rounded Acme 1:1 0.05" ±0.0006" per in. Brinell 160 90,000 6350K703 157.70

3/8"-20 6 ft. 1 Rounded Acme 1:1 0.05" ±0.0006" per in. Brinell 160 90,000 6350K134 186.56

3/8"-40 3 ft. 1 Rounded Acme 1:1 0.025" ±0.0006" per in. Brinell 160 90,000 6350K702 157.70

3/8"-40 6 ft. 1 Rounded Acme 1:1 0.025" ±0.0006" per in. Brinell 160 90,000 6350K137 186.56

1/2"-8 3 ft. 1 Rounded Acme 1:1 0.125" ±0.0006" per in. Brinell 160 90,000 6350K713 203.44

1/2"-8 6 ft. 1 Rounded Acme 1:1 0.125" ±0.0006" per in. Brinell 160 90,000 6350K125 247.56

1/2"-10 3 ft. 1 Rounded Acme 1:1 0.1" ±0.0006" per in. Brinell 160 90,000 6350K712 203.44

1/2"-10 6 ft. 1 Rounded Acme 1:1 0.1" ±0.0006" per in. Brinell 160 90,000 6350K21 247.56

1/2"-20 3 ft. 1 Rounded Acme 1:1 0.05" ±0.0006" per in. Brinell 160 90,000 6350K711 203.44

1/2"-20 6 ft. 1 Rounded Acme 1:1 0.05" ±0.0006" per in. Brinell 160 90,000 6350K135 247.56

5/8"-10 3 ft. 1 Rounded Acme 1:1 0.1" ±0.0006" per in. Brinell 160 90,000 6350K718 237.94

5/8"-10 6 ft. 1 Rounded Acme 1:1 0.1" ±0.0006" per in. Brinell 160 90,000 6350K129 352.55

3/4"-10 3 ft. 1 Rounded Acme 1:1 0.1" ±0.0006" per in. Brinell 160 90,000 6350K722 316.09

3/4"-10 6 ft. 1 Rounded Acme 1:1 0.1" ±0.0006" per in. Brinell 160 90,000 6350K131 453.83

Flange Nuts—Right-Hand Threaded

A

B

C

Flange nuts with wear-compensating internal O-ring or wear-compensating spring maintain a tight fit even when their threads begin to wear.

Flange

  Thread Size Lg. Dia. Dia. Wd. Ht. Thick. No. of

Thread Starts Thread Type Speed

Ratio Travel Distance

per Turn Mounting Hole

Ctr.-to-Ctr. Bolt Circle

Dia. Tensile

Strength, psi Dynamic Thrust

Load Cap., lbs. Each

Acetal Plastic

A 1/8"-20.8 1/2" 0.4" __ 3/4" 13/32" 1/8" 1 Rounded Acme 1:1 0.048" 39/64" __ 9,000 25 6350K682 $20.08

A 1/8"-41.7 1/2" 0.4" __ 3/4" 13/32" 1/8" 1 Rounded Acme 1:1 0.024" 39/64" __ 9,000 25 6350K681 20.08

A 9/64"-20.8 1/2" 0.406" __ 3/4" 13/32" 1/8" 1 Rounded Acme 1:1 0.048" 39/64" __ Not Rated 25 6642K22 20.05

A 9/64"-41.7 1/2" 0.406" __ 3/4" 13/32" 1/8" 1 Rounded Acme 1:1 0.024" 39/64" __ Not Rated 25 6642K21 20.05

A 7/32"-20.8 1/2" 0.406" __ 3/4" 13/32" 1/8" 1 Rounded Acme 1:1 0.048" 39/64" __ Not Rated 25 6642K24 20.05

B 1/4"-20 1" 0.5" 1" __ __ 3/16" 1 Rounded Acme 1:1 0.05" __ 3/4" 9,700 50 6350K171 19.90

B 1/4"-40 1" 0.5" 1" __ __ 3/16" 1 Rounded Acme 1:1 0.025" __ 3/4" 9,000 50 6350K683 19.69

B 3/8"-10 1" 0.625" 1 7/64" __ __ 3/16" 1 Rounded Acme 1:1 0.1" __ 7/8" 9,700 75 6350K33 30.18

B 3/8"-20 1" 0.625" 1 7/64" __ __ 3/16" 1 Rounded Acme 1:1 0.05" __ 7/8" 9,700 75 6350K172 27.30

B 3/8"-40 1" 0.625" 1 7/64" __ __ 3/16" 1 Rounded Acme 1:1 0.025" __ 7/8" 9,700 75 6350K175 27.30

B 1/2"-8 1 1/2" 0.75" 1 1/2" __ __ 3/16" 1 Rounded Acme 1:1 0.125" __ 1 1/8" 9,700 150 6350K163 29.65

B 1/2"-10 1 1/2" 0.75" 1 1/2" __ __ 3/16" 1 Rounded Acme 1:1 0.1" __ 1 1/8" 9,700 150 6350K41 32.77

B 1/2"-20 1 1/2" 0.75" 1 1/2" __ __ 3/16" 1 Rounded Acme 1:1 0.05" __ 1 1/8" 9,700 150 6350K173 29.65

B 5/8"-10 1 1/2" 0.875" 1 1/2" __ __ 3/16" 1 Rounded Acme 1:1 0.1" __ 1 3/16" 9,700 220 6350K167 32.38

B 3/4"-10 2" 1.125" 1 51/64" __ __ 1/4" 1 Rounded Acme 1:1 0.1" __ 1 7/16" 9,700 350 6350K168 43.68

Acetal Plastic with Wear-Compensating Internal O-Ring

A 9/64"-20.8 1/2" 0.406" __ 3/4" 13/32" 1/8" 1 Rounded Acme 1:1 0.048" 39/64" __ Not Rated 5 6642K32 27.75

A 9/64"-41.7 1/2" 0.406" __ 3/4" 13/32" 1/8" 1 Rounded Acme 1:1 0.024" 39/64" __ Not Rated 5 6642K31 27.75

A 7/32"-20.8 1/2" 0.406" __ 3/4" 13/32" 1/8" 1 Rounded Acme 1:1 0.048" 39/64" __ Not Rated 5 6642K34 27.75

Acetal Plastic with Wear-Compensating Spring

B 3/4"-10 2 45/64" 1.563" 2 13/32" __ __ 5/16" 1 Rounded Acme 1:1 0.1" __ 2" 9,700 150 6350K206 157.19

C 1/4"-20 1" 0.5" 1" __ __ 3/16" 1 Rounded Acme 1:1 0.05" __ 3/4" 9,700 5 6350K208 34.13

C 3/8"-10 1 29/32" 0.703" 1 1/2" __ __ 3/16" 1 Rounded Acme 1:1 0.1" __ 1 1/8" 9,700 10 6350K53 45.04

C 3/8"-20 1 29/32" 0.703" 1 1/2" __ __ 3/16" 1 Rounded Acme 1:1 0.05" __ 1 1/8" 9,700 10 6350K209 40.75

C 3/8"-40 1 29/32" 0.703" 1 1/2" __ __ 3/16" 1 Rounded Acme 1:1 0.025" __ 1 1/8" 9,700 10 6350K213 40.75

C 1/2"-8 2" 0.891" 1 39/64" __ __ 17/64" 1 Rounded Acme 1:1 0.125" __ 1 1/4" 9,700 25 6350K201 53.23

C 1/2"-10 2" 0.891" 1 39/64" __ __ 17/64" 1 Rounded Acme 1:1 0.1" __ 1 1/4" 9,700 25 6350K61 53.23

C 1/2"-20 2" 0.891" 1 39/64" __ __ 17/64" 1 Rounded Acme 1:1 0.05" __ 1 1/4" 9,700 25 6350K211 53.23

C 5/8"-10 2" 1.063" 1 51/64" __ __ 17/64" 1 Rounded Acme 1:1 0.1" __ 1 3/8" 9,700 35 6350K205 65.73