Review on Stinger SPT521 Gauge Reducer Input by Ryan Person

As mentioned earlier, this adapter is too wide to fit any 4ga outlet and mine was no exception. I ended up having to use a metal file to shave the sides just enough for it to fit. Also, I had trouble finding heat shrink tubing with an inside diameter large enough to slip over the outside of the adapter. Again, as mentioned, this can lead to short circuit problems if you use an adapter on the power and ground terminals (since everything is metallic and conductive on the outside).