This Polar Chest strap is encased in 100% waterproof materials making it ideal for long and intense workouts. Not only is the transmitter waterproof, but it is also constructed with hygienic material. The adjustable elastic nylon strap provides true customization. Enjoy this lightweight, durable heart rate transmitter from Kettler.Verso 309Paso 309RPlug-in receiver not includedTransmits heart rate to a number of Kettler fitness equipment (TX1SP 211works only with above listed items. If you need a chest strap with plug-in receiver please see Cardio Pulse Set (item# 7937-600)Coach ERX 7Ergo RaceTX3EXT 7Paso 309R-400Assembly NoMaterial NylonType Heart Rate MonitorColor Black