air-flexx® valve extensions offer many advantages over conventional valve extensions due to their multi-layer construction: They are flexible, yet rigid enough to be used without rim holders (exception: air-flexx ® 315 mm, 415 mm and 1000 mm). The material is extremely durable and will not become brittle during the normal service life of a tire - and far beyond. air-flexx® valve extensions ensure that you can conveniently check the tire pressure at any time (information video).