heat treated alloy tool steel, one inch base fits wrench or bench vise. Thin wall construction allows use without removal of cones and locknuts. The FR-5G has 12 splines that are approximately 23.4mm across.
Capitol Hill Tool Library
http://sustainablecapitolhill.org/tool-library/
1552 Crawford Placehttp://sustainablecapitolhill.org/tool-library/
Seattle, WA, 98122
USA