A-B Rockwell Automation 847H-FG1A-RG00120. Incremental Encoder, 2.5" Diameter, Solid Shaft, Bell Housing and Coupler, 3/8 Bore Bellows Coupler, 4.5 5.5 V DC, 4.5 5.5 V Line Driver (TTL), Radial Exit, MS 10 Pin w/ Mating Connector, B leads A, CW, Z gated with BN, 120 PPR