Fitment: Marine Propeller Lock Set Compatible with Mercury, MerCruiser, OMC (3/4"- 16 Thread Size). Replaces Part Number 74039 Working Principle: The marine propeller lock set operates by replacing the standard propeller nut with a specialized locking nut that features a free-spinning collar. Prevents unauthorized removal using conventional tools Material: The is made from brass and hardened stainless steel, ensuring long-lasting durability. Provides maximum corrosion resistance, designed specifically for harsh marine environments and saltwater exposure Theft Prevention: Protects your expensive boat propeller from being stolen. The is designed to withstand heavy impact and tampering, especially when docked or stored. Advantages: Marine-grade ruggedized products prevent rust degradation over time and withstand extreme conditions. Ensures a snug and secure fit without affecting propeller performance Note: Please confirm the brand and model before placing your order; this part is not compatible with OE: 74040

Product Description:

Marine Propeller Lock Set (3/4"- 16 Thread Size) Compatible with Mercury, MerCruiser, OMC.

Fit for MerCruiser Alpha I

Fit for OMC Cobra and King Cobra

Fit for Mercury/Mariner 70 HP and larger (ex. 225 HP 4 stroke before 2005)

Fit for Mercury Bigfoot 40 HP, 50 HP, and 60 HP (4 stroke)

Replace Part Number#- 74039

Product Specification:

Style: Propeller Locks 

Thread Size:3/4-16"

Hex Size: 1-1/16

Overall Length:1.025"

Packaging: Set of 1 Lock, 1 Key, 1 Washer, and 1 Cap

Vantage：

1.Primary function: Prevents theft of your expensive propeller.

2.Secondary function: Replaces the standard propeller nut with a more secure alternative.

3.Peace of mind: Adds a layer of protection for boats stored at marinas or unattended docks.

4.Easy to install: Can be installed by the boat owner with basic tools and the included key.