Specifically designed for TSS loads that have become very popular with turkey hunters but will also shoot super tight patterns with HEVI-Shot, Copper Plated and Lead Shot. This extended choke tube allows for easy installation without the use of tools.Features.670 Constriction (12 GA Mossberg 835/935).650 Constriction (12 GA Remington, 12 GA Invector/Mossberg 500, 12 GA Invector Plus, 12 GA Beretta/Benelli Mobil, 12 GA Benelli Crio).560 Constriction (20 GA Remington, 20 GA Beretta/Benelli Mobil, 20 GA Benelli M2).390 Constriction (.410 Beretta/Benelli Mobil, .410 Remington, .410 Invector)