Pro-werks Easy Turn Filler Cap with O-Ring

1-5/8 Inch Fill Cap 1-1/4-12 Straight Thread Cap Weight: 1.06 oz. Without Lanyard Boss Includes O-Ring (Cap Replacement O-Ring is C73-749) 2 Inch Fill Cap 1-1/2-12 Straight Thread Cap Weight: 1.62 oz. Without Lanyard Boss Includes O-Ring (Cap Replacement O-Ring is C73-769) 2-3/4 Inch Fill Cap 2-1/4-10 Straight Thread Cap Weight: 3.32 oz. With Lanyard Boss, Accepts Lanyard Chain Kit Includes O-Ring (Cap Replacement O-Ring is C73-788-A) 4-1/4 Inch Fill Cap 3-3/4-8 Straight Thread Cap Weight: 7.86 oz. With Lanyard Boss, Accepts Lanyard Chain Kit Includes O-Ring (Cap Replacement O-Ring is C74-788-A) The lightweight, non-vented cap features positive grip finger notches that are easy to get a hold of. Prime 6061-T6 billet aluminum is precision CNC machined into a lightweight, attractively designed cap; featuring quick-start coarse threads. Each screw on Cap is fitted with a Buna O-ring; positive sealing and "radially squeezed" to hold the cap secure.  Your browser does not support our video.   Your browser does not support our video.   Fill Cap with O-Ring This design uses a radial squeeze action on a Buna O-ring for a secure seal. Precision machined quick-start coarse threads make using these caps a breeze. The large selection of Pro-werks’ mounting bungs are crafted from Steel, Aluminum or Stainless Steel and available in both weld and bolt-on styles. Great Caps. Great Colors. To compliment the color coordination of your project, the caps are finished off in Pro-Werks Brilliance anodized colors in your choice of Black, Red, Blue, or beautifully Micro-Polished aluminum – the finishes are impeccable! The Right Size Matters Easy Turn Fill Caps come in many sizes and are packaged as complete assemblies with your choice of one of the many versatile mounting options, or each component is also available separately Popular Uses: Custom-fabricated tanks Fuel cells Rear End housings Valve covers Overflow tanks Ice boxes for intercoolers Ballast tanks Inspection viewing ports Proudly Made in the USA Be sure to check out the entire line up - Billet aluminum Easy Turn Fill Caps are a Pro-werks specialty. You can always count on Pro-Werks to do it right! Customer Comments: "I use your bolt on caps and bungs on my carbon fiber Cummins common rail valve covers. Love the quality. Thank you." – Randy Davis, Owner of OldSkoolFab, Inc. "I upgraded my fuel cell to an Easy Turn fill cap assembly. It wasn't long until all my friends did the same. Great product!" – As shared with us at the PRI Show Frequently Asked Questions Q: How much do I need to tighten a fill cap? A: It is not necessary to bottom the fill cap into the bung−just adequately seat the O-ring. The radial squeeze action on the O-ring creates a positive seal and helps prevent the cap from coming loose. Q: What should I use to lubricate the Buna O-ring? A: Applied periodically, a light coating of Dielectric grease has proven to work well as an O-ring lubricant. Q: Is Buna rubber compatible with my fluid? A: Buna is a synthetic rubber compound suitable for use with many fluids. Buna components may need to be replaced by a material compatible with the specific chemistry of some fluids.