Schaefer Marine Twin Sheet Block f/1-1/4" T-Track - Black. Aluminum sheave runs on nomex/Teflon bearing for a low-friction high strength sheave. Articulating sheave allows for a proper lead. Pin stop makes adjustment simple. Specifications for Schaefer Marine Twin Sheet Block f/1-1/4in T-Track: Manufacturer: Schaefer Marine Color: Black Package Contents: Schaefer Marine Twin Sheet Block f/1-1/4in T-Track Schaefer Marine 32-97: Twin Sheet Block f/1-1/4" T-Track - Black