DER SCHATZ  Elastic bands are lightweight, portable and very durable.
Wrap around any part of your body and make your workout more effective.
They also have varying levels of resistance, making them amazing for at-home workouts, or for when you're traveling and don't have access to a gym.
The band loops come in 3 pcs set resistance levels.
Heavy 33 cm (13-15 kg)
Medium 38 cm (8-10 kg)
Light 43 cm ( 3-5 kg) 
Designed for the people who need adjust the strength while doing exercise workout.