These pins are sold as a pair. Pistol models only require one pair, rifle models have three pins so you would need two pairs. They are made of hardened alloy steel, much smoother, harder and more durable than a standard pin. They are also a full .125" diameter compared to Crosman's at .124" so they fit better reducing wobble. They fit all 1377, 1322, 1300KT, PC77, 2289G Backpacker, 2240, 2250, 2260, 2300T, 2300S, 2300KT, 2400KT, 1701P, 1720T, Marauder Pistol, 1720T, 1701P, Discovery, Maximus, Fortitude and related models that use the same trigger groups.