Athene Arms checks out this BPW MCX SURG URG Upper receiver Kit made for the VFC M4 GBB Series. This product is designed specifically for the VFC M4 GBB series and lower receiver group, intended for Airsoft use only. Due to potential batch tolerances, different lower assemblies may require modifications, so having DIY skills is essential. The Airsoft tracer, which can be installed in a 14mm CCW thread adapter at the front of the tube base, must be less than 38mm in diameter and 125mm in length.

The specifications include materials such as steel, 6061 aluminum alloy, metal, nylon, and rubber. The upper receiver kit measures 490mm in length and weighs 1410g with internal parts, all made in Taiwan. The package includes a SURG style upper receiver kit with an upper receiver, gas block, outer barrel with Airsoft 14mm CCW threaded, 300mm inner barrel, Hop Up set, bolt carrier group, and charging handle. Additionally, it comes with a SURG SLX style Airsoft dummy suppressor, a SURG style stock adapter, and an Airsoft folding stock.