WeldingCity 5-pk Gas Diffusers 51 for Lincoln Magnum and Tweco Mini/#1 MIG Welding Guns Premium quality Lincoln/Tweco style MIG gas diffuser 51 Work with 11 series contact tips in Tweco #1 and Lincoln Magnum MIG guns. You get Five (5) gas diffusers 51 at this price We use U.S. Postal Service (USPS) as main carrier. Please provide a USPS deliverable address.