We performed an update overnight, Please refresh your browser to view the website pages properly! 


$26.29 ea
Quantity Price (USD)
1 $26.29 ea
20 $15.77 ea
60 $13.15 ea
100 $11.83 ea
250 Request Quote
In Production Lead Time: 1 Week or Less
Ruland MSPK-12-A, 12mm Two-Piece Shaft Collar, Aluminum, Clamp Style With Keyway, 28mm OD, 11mm Width


Ruland MSPK-12-A is a two-piece shaft collar with a 12mm bore, 4mm keyway, 28mm OD, and 11mm width. The clamp style design does not mar the shaft, is easy to remove, and is indefinitely adjustable. It is commonly used for guiding, spacing, stopping, mounting, and component alignment. The keyway prevents slippage on the shaft when the shaft collar is used for positive drive. Equipment manufacturers benefit from the tightly controlled face to bore perpendicularity of Ruland shaft collars, TIR of ≤ 05mm. Perpendicularity is critical for alignment when the shaft collar is used as a load bearing face, mechanical stop, or for mounting components such as gears or bearings. Proprietary processes have been developed by Ruland to maintain superior fit, finish, and holding power. MSPK-12-A is stamped with the Ruland name and bore size for ease of identification. Halves are mated throughout the manufacturing process for proper fit and alignment. Forged screws test beyond DIN 912 12.9 standards to ensure maximum holding power. MSPK-12-A is machined from solid bar stock to a fine burr free finish and sourced exclusively from North American mills. Ruland uses high grade 2024 aluminum for increased screw seating torque. It is RoHS2 and REACH compliant and manufactured in our Marlborough, MA factory under strict controls using proprietary processes.



Bore B

12 mm

Bore Tolerance

+.050 mm / +.012 mm

Keyway K

4 mm

Width W

11 mm

Outer Diameter OD

28 mm

Width Tolerance

+.076 mm / -.254 mm

Clearance Diameter C MAX

32.0 mm

Fastening Hardware

Forged Clamp Screw

M4 x 12

Screw Material

Alloy Steel

Hex Wrench Size

3.0 mm

Screw Finish

Black Oxide

Seating Torque

4.6 Nm

Screw Location R

10.01 mm

Number of Screws

2 ea

Additional Information

Material Specification

2024-T351 Aluminum Bar


-40°F to 225°F
-40°C to 107°C

Finish Specification



Ruland Manufacturing

Country of Origin


Weight (lbs.)




Product Notes

Note 1

Performance ratings are for guidance only. The user must determine suitability for a particular application.

Prop 65

WARNING This product can expose you to the chemical Ethylene Thiourea, known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.

ISO 9001:2015


Conflict Minerals






We found other products you might like!


© 2018 Ruland Manufacturing Co., Inc. All rights reserved