Exhaust Bellows Boot compatible with Mercruiser Bravo 1, Bravo 2, Bravo 3, Alpha One, and Gen II outdrives.Package includes 1 bellows and 2 stainless steel clamps.Replaces OEM part numbers 18654A1, 18654B1, 32734, 32734A3, and 8M0124227.Also replaces Sierra part number 18-2750.Fits models including Alpha I, Gen II, Bravo I, Bravo II, Bravo III, #1, R, MR, TRS, and Blackhawk.Bellows measures approximately 2.5 inches inner diameter at each end and 5.25 inches in length.Compatible with the following Mercruiser engines: 120/140 (1978–1982), 165 (1978–1981), 260 (1978–1982), 470 (1978–1982), 485 (1980–1982), 898/228 (1978–1982), Alpha One Gen I (1983–1990), Alpha One Gen II (1991–present), Bravo I (most models), Bravo II (most models), and Bravo III (most models).