Heart rate monitor strap. Please use as a spare. Do not use a dryer. Compatible with heart rate monitors with a terminal width of approximately 45mm. See the second image. The item in the last image is all that is included. The heart rate monitor unit and instruction manual are not included. Length: Approximately 60cm when fully contracted Approximately 90cm when fully extended, It can be stretched by about 14cm with the elastic band from there, so theoretically, it can be worn around the torso up to about 104cm. (Polar Garmin CATEYE Wahoo, etc.) Compatible with various brands. Not an authentic product. Heart rate chest strap ANT+ Bluetooth Specialized, Cannondale, Trek, Merida, Giant, Bianchi, Pinarello, Colnago, and other manufacturers' road bikes, cross bikes, mountain bikes, e-bikes, etc. for training, hill climbing, indoor training, cycling, casual rides, bike commuting, Zwift, long rides, enduro races, and gran fondos. Heart rate monitoring is also useful for diet, weight loss, stamina, health management, and maintaining motivation. It can also be used for marathon runners, ekiden runners, sprinters, joggers, trail runners, and other sports heart rate monitors, as long as the width is approximately 45mm. This is a new product, but as it is an overseas product, there may be minor scratches, scuffs, or fraying from the manufacturing process. If you are concerned about this, please refrain from purchasing. Packaging, boxes, and instruction manuals are not included. It will be shipped in a simple package with a brown envelope. If you are concerned or are sensitive about this, please refrain from purchasing.