A-B Rockwell Automation 847T-DN1A-RQ02750. Incremental Encoder, 2" Diameter, Solid Shaft, Standard Square Flange, 3/8 Diameter Shaft with Flat, 4.5 5.5 V DC, 4.5 5.5 V Line Driver (TTL), Radial Exit, 5 m (16.4 ft) Cable, B leads A, CW, Z gated with BN, 2750 PPR