Designed to fit low in the block to clear firewall and intake combinations. CNC machined billet alum housing and Dupont Rynite base is designed for standard Chevy blocks. Adjustable slip collar for engines with modified deck heights. 0.500" taller for extra tall Chevy based engine blocks. Oversized polished steel shaft with a QPQ coating for friction reduction. Shaft is guided by a sealed ball bearing and an extra long sintered bushing. Special oil tract improves lubrication to the dist and cam gear. O-ring seals can be added to modified blocks to improve oil pressure control. Supplied with small, low crab style dist cap, rotor & bronze gear. Must be used with an MSD Crank Trigger & MSD Ign Control. No CARB Exemption Order Number.