MERCURY, MARINER: Bigfoot/25 HP 4-Stroke 1999-2005 1994 - 2002 30 HP 2-Stroke 1999 - 2005 30 HP 4-Stroke 1994 and Newer 30 HP (Sea Pro/Marathon) From 1984 through 1989, 35 HP was available. 1977 and Newer 40 HP 2-Stroke (Includes Model 402) 1997 and Newer 40 HP 4-Stroke (Not Bigfoot) 1977 and Newer 40 HP (Sea Pro/Marathon) From 1986 until 1989, the 45 HP model was available. All Years 48 HP (Mariner ) 1977 and Newer 50 HP 2-Stroke (Includes Model 500) 1995 and Newer 50 HP 4-Stroke (Not Bigfoot) 1995 and Newer Mercury/Sea Pro/Marathon 55 HP 1978 and Newer 60 HP 2-Stroke 2001 and Newer 60 HP 4-Stroke (Not Bigfoot) Until 1983, 70 HP (including Model 700) 13 Tooth Spline & Thru Hub Exhaust CHRYSLER, FORCE, US MARINE: From 1995 to 1998, the 40 HP model was available. 1995 - 1998 50 HP From 1991 until 1995, 70 HP was available. 1996 - 1998 75 HP 13 Tooth Spline & Thru Hub Exhaust Key features: Number of Blades: 3 Number of Splines: 13 Specifications: Rotation: Right-Hand Aluminum Engine: Chrysler, Force, Mercury, Mariner, U.S. Marine Hub Kit: Not necessary (rubber pressed in the hub)