This is a brand new rear wheel sprocket with 5 hole.
Part # 37-4046, W4046
Sprocket teeth: 50
Chain size: 530
Chain Pitch: 5/8″ X 3/8″
Fits: Triumph T150 Trident with conical hub from 1971-74
BSA A75 Rocket 3 with conical hub from 1971-72