Laminar Flow Series, Designed for superior gas coverage for TIG welding. With the new design and diffuser, premium gas coverage will be the best available. Now available in 4,5,6,7,8,10 with the Diffuser available in 1/16, 3/32, 1/8 and 5/32. The LF Series will soon be available in the XL, XXL, Quartz, Large Diameter, GL1718 as well as the Collet Body cups, providing better than gas lens gas coverage for collet body applications.THIS KIT CONTAINS THE PATENTED WELDING CUP ADAPTER WITH DOUBLE O-RING SEAL, (2)THERMAL SPACERS, (2) HIGH-TEMPERATURE O-RING SEALS AND 6 LAMINAR FLOW WELDING CUPS WITH DIFFUSER.WELDING KIT INCLUDES: # 4, #5, #6, #7, #8, #10 920 Series Gas Lens Welding Cups with Diffuser (1/16, 3/32, 1/8, 5/32)