Left Hand Thread B-Size Argon Adaptor fitting  (5/8-18 LH Female thread) x 1/4" Male Pipe Thread.   Thread pitch is 5/8-18 LH internal thread.  These fittings fit water cooler  hose fittings for most TIG and MIG welding systems. These are new fittings made from brass. Superior PN A-405 Same as Western Enterprises AW-15 Fitting.   Not responsible for the end use of this product. We Combine Shipping using actual shipping charges and no handling fees.  Request an invoice for multiple shipments and we will calculate the shipping amount E-mail us if you can't find the welding fittings that you need.  We can get the full line of welding fittings including bulk gas supply fittings. BRW Technologies, LLC standard terms and conditions apply.  See our terms and conditions at brwtechnologies.com