Heidenhain 1144018-04 (ERM 2489) Scanning head for Incremental built-in Encoder w/ magnetoresistive scanning, 1024 line count, 1Vpp Line Count (1024) Grating period (395.00um) Drum outside diameter: 128.75 mm Reference mark (analog) Power supply (5V±10%) Output (1Vpp) Cable length (4.5mm)