The is the number one selling marine mechanical seal worldwide and is installed as standard equipment by many reputable boat builders. It is recognized as the premiere retrofit seal on the market. Certified by Bureau Veritas, ABS & Rina, it eliminates maintenance, constant adjustment, and cost associated with traditional packing type glands. The helps to eliminate water in the bilge and wear to the propeller shaft. It can be easily retrofitted and is available for shafts ranging from 3/4 to 6.Specifications. Shaft Diameter: 1-1/2. Stern Tube Diameter (D): 2-1/2 to 2-5/8. Total Length (A): 9.175. Total Length (compressed) (Compressed A): 8.175. Rotor Diameter (B): 3.75. Carbon Cuff Diameter (C): 3.25. Stern Cuff Length (E): 2Features. Mechanical face seal. Eliminates water in the bilge. Reduces wear to the propeller shaft. Easy retrofit installation. Available for various shaft sizes