[Golden Eagle] M870 Gas Pump Action Shotgun gas tank[BLK]

I bought this tank based on the sixmm website saying it was compatible with the TM 870. The tank arrived but leaked from both the fill valve and the back end of the tank where the TM ones leak from. It is also not compatible with the TM 870 as the release valve bayonet on the Golden Eagle tank is shorter than the TM ones (see picture. Golden Eagle tank is the left tank with brass, TMs are the women the right) and so the TM stock does not reach to push and release the gas.