DUCATI /NCR/900SS SPECIAL BUILDERS FUEL TANK OUTLET UNION FOR FUEL TANK FOR VENTING TO AIR/FUEL TANK MUST HAVE HOLE IN FRONT TO FIT THIS UNION AS IT IS CLAMPED FROM  BOTH SIDES ON FLAT SURFACE TO SEAL-WILL NOT FIT UNLESS A HOLE IS MADE AT FRONT OF FUEL TANK IDEAL FOR THOSE HAVING A SPECIAL TANK MADE-ALSO SUPPLIED IS A VENT TUBE INCORPORATING A ONE WAY NON RETURN VALVE IN TUBE..The GIOVANNIMOTO  trademark is your guarantee of the highest quality products and a full money back guarantee is offered.Postage/packing/insurance for uk 1st recorded,insured £3.50/Overseas airmail recorded,insured for Europe£9Americas£10/Australia,New Zealand and Japan £11.Paypal only for overseas.Thanks for looking.