For Shopsmith Band Saws. Contains: 2 guide blocks 3/8" x 3/8" x 1" and 2 guide blocks 3/8" x 1/4" x 1-1/2". Cool Blocks blade guides are made from a high tech, non-metallic composite material, "Graphite Impregnated Phenolic Laminate" which contains three synthetic dry lubricants that lubricate the blade but do not make it oily. Metal guide blocks create metal to metal contact, causing heat, friction, premature blade wear and breakage. Imitation plastic guides melt and offer no lubrication. Cool Blocks blade guides allow blades to run cooler and last longer with less friction. They improve the cutting performance of any blade width, but are most effective with 1/16″ and 1/8″ wide blades for tight radius work. Made in USA