Banish Fixed Barrel Spacer Banish 45 Black. The Fixed Barrel Spacer replaces the spring inside the Nielsen device in the BANISH 45 and should only be used on a fixed barrel firearms. Most commonly fixed barrel spacers are used on hosts such as pistol caliber carbines and subguns such as Sig MPX CZ Scorpion and Kriss Vector. Specifications for Banish Fixed Barrel Spacer: Manufacturer: Banish Fabric/Material: Aluminum Color: Black Finish: Black Anodized Package Contents: Banish Fixed Barrel Spacer Banish 5968: Fixed Barrel Spacer Banish 45 Black