AIR CLEANER 2″X4″ FINNED 2 5/8 Base Vintage Speed with tri bar Vintage Speed’s own 2″x4″-finned top classic air cleaner –Our unique base design allows you to use the socket head set screw or attach with 1/4″-20 stud on carbs with drilled boss(roch 2gs etc.)Show polished cast alum. with a modern fram element behind a plated screen and a three bar spinner nut. The classic look you want with the engine protection you need. This is the finest air cleaner you can buy for the $. I will have 2 5/16″ bases for this air cleaner for you inline 6 guys. You need to tell me in the shipping instructions if you need the 2 5/16″ base.