Olson Saw CB50070BL 12-Inch Delta/Jet Band Saw Accessory Cool Blocks For Delta 10" 28-140, 16" 28-560 3-wheel and 12" 28-190 Band Saws Contains: 4 guide blocks 5/16" square x 3/4" Cool Blocks blade guides are made from a high tech, non-metallic composite material, "Graphite Impregnated Phenolic Laminate"