Mercury - Pistol Grip Grease Gun Maintenance Tool For 8 oz Grease Cartridges 37299A2. Overview. Make lubrication tasks cleaner and easier with the Mercury Marine 37299A2 Pistol Grip Grease Gun. Designed for use with 8-ounce tubes of Mercury 2-4-C or Extreme Grease, this compact, portable gun helps you service your boat's moving parts quickly and without mess. The pistol-grip handle gives you precise control, while the flexible feed hose lets you reach awkward fittings with ease. Whether you're g