Stan39s tubeless system converts your existing wheel set to tubeless allows you to use either standard or tubeless tyres note rim strips feature presta valve stems fits most standard mountain bike rims mavic 221 317 517 519 223 and sun 0 xc ufo sub4 etc also fits bontrager 2939er disc rims this kit includes two molded rim strips with presta removable valve cores one pint of tire sealant with a 60g scoop and spout one 10 yd roll of spoke tape notubescom decal