Product Name: Airsoft Charging Handle Spring/Tension Lever Spring for many M4 modelsSpanner lever springs unfortunately only have a limited lifespan and can be quickly overloaded and therefore extended if the upper and lower receivers are disassembled carelessly. The search for the right replacement spring and its availability is often a problem. That is why we offer this universal Charging Handle Spring. It fits most M4/M16 or AR15 and models. Reduction of reverberating noises when shot The spring can be installed easily tensioned. This even helps to minimize “clinking” or resocking on some models. For this reason, the spring is also lightly coated with a fully synthetic grease. Technical data and scope of delivery Dimensions: (total length, diameter, wire thickness) 50 mm x 4 mm x 0.6 mm Material: stainless steel Long life and high recovery force