NSN# 8415-01-544-6870. This is the "Original Viper". All other Viper models are the exact same in shape and size, only difference is the base fabric used for garment construction, nylon cord grid work spacing and a few other smaller features. This Original Viper is the most feature rich Viper available from Tactical Concealment. Mid-weight Supplex base fabric, tight grid cord spacing and can accommodate the optional backdrape.