Used on high speed bench grinders usually with buffing compounds to polish metal. Sisal mops are the coarsest fibre similar to that in rope and act as a strong and aggressvie carrier for your choice of cutting compound.
Spine, Stiffener, for 9 inch (228mm) DOVETAIL SAW, BRASS, 3/16 x 5/8 inch (4.76 x 15.88mm), Slot Depth 0.250 inch (6.35mm), for Blade Thickness of 0.015 inch (0.381mm)