The Blue Bird Bellow Kit is a reliable replacement for OEM M66-7091-0405 and M66-6541-0405. Constructed with 321 stainless steel, this kit features a 4-inch diameter and 13.5-inch long bellow, along with a 5-inch diameter flange and flare. The kit includes one bellow, two rings, and two clamps, making it practical and convenient. Designed to fit most Blue Bird buses, this kit compares to OEM M66-7091-0405 and M66-6541-0405. With its durable construction and comprehensive components, the Blue Bird Bellow Kit is a reliable choice for your bus maintenance needs.