These slim master cylinders are 100% machined billet aluminum for extra strength in a more compact size. They have standard 2-1/4" pattern used by most brake companies so they will mount to most pedal assemblies and firewalls. The mounting flange can rotate to be a vertical bolt pattern or horizontal pattern. Uses DOT 3, DOT 4 or DOT 5.1 brake fluid. The inlet and outlet are tapped for standard 1/8" NPT fittings.

Size comparison for reference:

Master cylinder body width:
Remote reservoirs master cylinder 1-5/8" wide
Slim line master cylinder 1-5/8" wide
Short standard width master cylinder 2-1/4" wide
Tall standard width master cylinder 2-1/4" wide

Master cylinder total height including the round cap:
Slim line master cylinder aprox. 3-1/2" tall
Short standard width master cylinder aprox. 4-3/8" tall
Tall standard width master cylinder aprox. 5" tall