Spring Chest Expander - a Classic for Strength Training The expander is one of the best-known and most popular training devices. And rightly so. After all, the fitness device can be used in a variety of ways to build muscle. It is also suitable for amateur athletes who only occasionally want to do something for their fitness. The 5-way adjustable chest expander from Gorilla Sports is perfect for toning the muscles in your chest, shoulders and arms. It offers a tensile force of around 10 kg per resistance band and can be comfortably tensioned thanks to its solid hardened plastic handles. The Features of the Chest Expander from Gorilla Sports at a Glance: 5-way adjustable Approx. 10 kg tensile force per resistance band W x H: 16.5 x 2.3 cm Handle area (L x W x H): approx. 17 x 12.5 x 3 cm Grip area approx. 13 cm long, diameter 32 mm Resistance bands approx. 63 cm long, diameter 6.6 mm Colour: black, grey, yellow Weight: approx. 400 g Material: plastic handles, rubber bands Possible Uses for the Expander After a warm-up phase, the expander from Gorilla Sports can be used primarily to strengthen the muscles in the upper body area. The bicep curl, for example, is suitable for training the upper arm muscles. Other well-known exercises are the side raise for the shoulder muscles and the butterfly for the chest muscles.