www.ReplicaAirguns.com Type: Airsoft Rifle. Manufacturer: BARRA. Model: Black Ops M4 Viper MK5 Materials: Mostly plastic. Weight: 4.8 pounds (2.2 kilograms). Length: 29-32.5 inches (737-825.5mm) Barrel Length: 12 inches (305mm) inner 6.08mm non-rifled. Propulsion: AEG. Action: Semi & Full Auto SAO. Ammunition Type: 6mm Airsoft BB's. Ammunition Capacity: Mid Cap 300 rounds. FPS: 420 with .12 gram Airsoft BB’s. Every once in a while you come across an underdog type Airgun that on paper and based on low cost you are not expecting to see amazing results from. The BARRA Black Ops M4 Viper MK5 AEG Airsoft Rifle is one such AEG Airsoft Rifle that overachieved my expectations by a lot, and I would say performed as well as any AEG Airsoft Rifle out there at even much higher price points. All of my testing was performed using the included 8.4 volt battery which worked well but I did find the rate of fire was a bit slower than if I was using a higher volt 11.1 volt battery. My advice if you do end up picking up the BARRA Black Ops M4 Viper MK5 AEG Airsoft Rifle and want a higher round per minute full auto, then at any time you can upgrade your battery and charger to a higher volt one. So what are you waiting for? Read Full Review: www.replicaairguns.com/posts/2023/7/27/barra-black-ops-m4-viper-mk5-aeg-airsoft-rifle-field-test-review Buy the BARRA Black Ops M4 Viper MK5 AEG Airsoft Rifle in Canada: https://www.replicaairguns.ca/the-viper-airsoft-aeg-rifle Buy Barra AIrguns in the US: https://www.replicaairguns.us/barra-airguns