Uni "Dual throat" pod with Eurethane end. ID: 1 5/8(43mm)-1 3/4" (46mm). This pod filter features a black Uerethane end cap, black foam element, black urethane snout with a stainless clamp. Jetting change or carburetor upgrade is normally necessary to achieve maximum performance. This new series uses a 5/16"wide clamping area to fit all popular carburetor models.