Arex Delta Extended Magazine Release Kit Ambidextrous Black 503822. 1 & All Delta Gen.2 models. The button is extended to make releasing the magazine a lot easier but still fit to all BGs and most aftermarket holsters available. Specifications for Arex Delta Extended Magazine Release Kit: Manufacturer: Arex Color: Black Package Contents: Arex Delta Extended Magazine Release Kit 1x Delta Extended Mag. Release Button (choose the side of extension) 2x Delta magazine catch spring (1x OEM 1xLight) Arex 503822: Delta Extended Magazine Release Kit Ambidextrous Black