The 01070-921 is an HS35 incremental optical encoder featuring a hollow shaft design that combines rugged, heavy-duty construction with sealed environmental protection. It accommodates shafts up to 1.00 inch in diameter and includes dual bearings and shaft seals rated for NEMA 4, 13, and IP65 environmental standards when ordered with appropriate sealing options. The encoder operates over a temperature range of 0°C to 70°C (with extended temperature testing available up to 105°C) and withstands shock loads of 50 g's for 11 milliseconds and vibration from 5 to 2000 Hz at 20 g's. It is available with optional dual output capability to provide redundant signals, dual resolutions, or independent controller feeds from a single encoder. Common applications include motor feedback and vector control, printing industries, robotic control, oil service industries, and web process control.