A-B Rockwell Automation 847T-DL1A-RH02500. Incremental Encoder, 2" Diameter, Solid Shaft, Standard Square Flange, 10 mm Diameter Shaft with Flat, 4.5 5.5 V DC, 4.5 5.5 V Line Driver (TTL), Radial Exit, MS 10 Pin w/o Mating Connector, B leads A, CW, Z gated with BN, 2500 PPR