The standard is the length of the line, it is recommended to pull it to less than half, longer and better! It is recommended to pull less than half ,if pull it over we do not waranty to rebound.

wire diameter is about 8mm

"strecth 1 meter" is processed by 3 meter wire, and the spring part is about 0.3 meter.

"strecth 2 meter" is processed by 4 meter wire, and the spring part is about 0.4 meter.

"strecth 3 meter" is processed by 5 meter wire, and the spring part is about 0.5 meter.

"strecth 4 meter" is processed by 6 meter wire, and the spring part is about 0.6 meter.

By analogy, each stretched length is added 2 meters, please note when you buy, as long as Knowing that your use distance is to open the length,

Generally, the spring part is 1 meter, and the opening is about 5-6 meters.

Model Number: Spring Wire

Package Include: 1 x Red Spring Power Cord Cable