1-3/8 Inch Billet Aluminum Roll Bar Mount Nitrous Express NX 11014 - USA-NX-11014 - These Bar mounts are constructed from Billet Aluminum and allow mounting of the following parts: NX Billet Aluminum Ball Valve (part # 15159) Standalone Battery Mounts (part # 15934) or Billet Bottle Bracket (part # 11108B). This Billet Aluminum Bar Mount allows the listed items to be mounted securely on a 1-3/8” (1.375") bar. With this you can rest assured that whatever you mount with these will be safe and secure. Specification: Bolt Size - 1/4” - 20 thread Mounting Hole Spacing - 2-5/8”