Filter Adapter is made to mount a 2.5" ID air filter to your Tillotson Carburetor. Each piece is CNC machined from 6061-T6 Aluminum and includes mounting hardware. Fits Tillotson HL-334A and HL-334AB Legal for TAG RACING. (Approximate 2.5" OD x 1.178" ID bolt spacing 1.750" fitted 10-32; check your air filter for fitment.)