Chantelle Soft Stretch Seamless Thong Panty (2649). The Chantelle Soft Stretch Seamless Thong Panty 2649 is a slick microfiber thong with seamless edges and sewn-in cotton crotch gusset. Chantelle's Soft Stretch Seamless Thong Panty is made of polyamide/elastane/cotton.