This lightweight, non-vented cap features positive grip finger notches and quick-starting course threads. Caps are available in anodized black, red, blue, or polished aluminum. Each is standard with a radial squeeze o-ring seal. Choice of weld-in bung (aluminum and steel) or bolt-on bung (aluminum only).Pit Stop USA offers Pro-Werks Aluminum 2-3/4" Black Cap w/ Weld-In Steel Bung - 2-1/4 -10 Thread 2-3/4" O.D. Bung C73-770 at low everyday prices. Be sure to check out all of our products from Pro-Werks including Pro-Werks Oil Tank Caps and Pro-Werks Steel Weld-In Bungs w/ Cap.