Presta valves are skinny (6mm in diameter) needle-like internal tube valves you’ll uncover on essentially all road bikes and dearer mountain bikes. The Schrader is the standard valve you discover on auto tires and plenty of bicycle inner tubes. Some pumps, for instance this Silca Gravelero, function reversible chuck heads. https://bookmarkinglog.com/story19740572/the-basic-principles-of-prestashop-live-chat-support