This blank (undrilled) baseplate accepts any ITG JC50 Large Dual Carburetor Megaflow Air Filter (Part No. 3817-050, sold separately). It is ready for you to drill to match whatever intake pattern you have. Requires three Clip-On Receptacles (Part No. 3817-002, sold separately) to accept the quick-release mounting hardware on the filter. Sold individually.
The ITG Megaflow JC50 filter measures 5.8" wide x 17.2" long, with a red plastic band around the top and bottom of the filter element.