Designed primarily for competition use; Billet-aluminum housing, ball-bearing guide and adjustable mechanical-advance assembly; Magnetic pickup provides accurate trigger signals to Chevrolet; CDI Ignition Box (not included); Uses a standard Chevrolet V-8 cap and rotor; Will clear most induction systems; Slip collar that can be adjusted to make up for block or head machining, or a tall-deck Bowtie block