Oxford cloth. SECURE 3-POINT FIXED DESIGN: Protect your bottles from falling off as you ride - the bike bottle holder can be easily installed with just three adjustable velcro straps, keeping the water bottle safe and stable even on rough roads. EASY INSTALLATION: Cup holder fits 0.9'' to 2'' bar. No tools required, just install by your hand, an installation video on the listing. WITH TIGHTENING DRAWSTRING: Adjustable drawstring design for almost kinds of cups and water bottles. Perfectly hold your 12-32 oz cans of beer, large cups, coffee mug, soft drinks, stainless steel bottle. MULTI-FUNCTION DESIGN: Not just a cup holder It is also ideal to hold bottle, cell phone, wall charger and much more to make your item organized. KEEP YOUR DRINK HOT/COLD: Our water bottle holder with PEVA thermal insulation layer is designed to keep your drinks cold in hot weather and warm in cold weather. This cup holder is made of premium Oxford cloth and 20CC PEVA, it is durable and can be used as your faithful bicycle companion.