The 63R128 is a high-resolution optical encoder from Grayhill's Series 63R, featuring 128 cycles per revolution with a 5-pin polarized connection and rugged ball bearing construction. It delivers standard quadrature 2-bit code output with Channel A leading Channel B by 90° ± 45°, operating at 5V ±0.25V with a maximum supply current of 30 mA and open collector outputs with integrated Schmitt Trigger and 10 kO pull-up resistors. The encoder is rated for 300 million rotational cycles and 5000 RPM shaft rotation, with an operating temperature range of -40°C to +85°C and mechanical life guaranteed for 10 years of continuous operation. Its sealed construction, stainless steel ball bearing (NSK ABEC 5), and robust materials make it suitable for precision motion control, industrial automation, and instrumentation applications requiring reliable position feedback.