E&C quick change M4 receiver set. This set comes with the special screw-in spring guide together with the stock tube that allows you to change the spring without having to remove the gearbox from the lower receiver. There are no trademarks.
Included:
- Upper and lower metal receiver
- Stock Tube
- QD Screw-in Spring guide
- Bolt catch
- Magazine catch
- Steel pin set
- Charging handle
- Bolt / dust cover