each v3 and v4 of the LDT HK416 are excellent, on the other hand the single shot in HK416 v4 might be much more secure as a result of mosfet put in. equally versions made available from AKgelblaster arrives with metal https://kkgelblaster.com/collections/best-sale/products/electric-m416-hk416d-assault-rifle-gel-ball-blaster