Cutting structure:the wear-resistance of teeth is enhanced with premium tungsten carbide hardfacing on the tooth surfaces for steel tooth bit Gauge structure:gauge protection with gauge inserts on the gauge surface of the cone, tungsten carbide inserts and hardfacing on the shirttail increases gauge holding capability. Sealed bearing structure:air cooling roller bearing package. Balls lock the conewhich reduces the probability of cone-dropping to minimum. Main type available:size: 5 7/8", 6", 6 1/2", 7 1/2", 7 7/8", 8 1/2", 9 1/2", 9 5/8", 9 7/8", 12 1/4", 14 3/4", 17 1/2", etc. Iadc code:1-- series, 2-- series, 3¡aseries Cutting structure:the wear-resistance of teeth is enhanced with premium tungsten carbide hardfacing on the tooth surfaces. Bearing structure:non-sealed roller bearing. Drilling fluid can enter the bearing directly for cooling; balls lock the cone which reduces the probability of cone cdropping to minimum Main type available:size: 2 3/8", 3", 3 5/8:", 3 7/8", 4", 4 1/2", 4 5/8", 4 3/4", 6", 6 1/2", 7 1/2", 7 7/8", 8 1/2", 9 1/2", 9 5/8", 9 7/8", 10 5/8", 12 1/4", 17 1/2", etc. Iadc code:1-- series, 2-- series, 3-- series Wooden boxes, 40kg