Hi Stacey, There is no adapter manufactured by ChiaoGoo to attach a US-6 (S) tip to a 50 inch (L) cable, sorry about that. The only cable your tips would attach to would be a 60 inch (S) cable, and with your 4 inch tips attached instead of 5 inch tips, the circular would measure 58 inches. Thank you for asking. Tracy, Handsome Fibers.