Injection molded ferrite ring is a common magnetic component widely used in various electronic devices, especially in encoders. An encoder is a sensor used to measure parameters such as position, speed, etc. of rotational or linear displacement. In encoders, injection molded ferrite rings are usually used as part of the magnetic material in conjunction with magnetic readheads for non-contact detection.
34.1x18x3mm single-sided multi-pole magnetized injection-molded ferrite ring for magnetic encoder
Guess you're asking, how many poles is this magnet ring?
62 and 64 poles.
Those who want a 128 pole can check it out: 128 poles and 126-poles multipole magnetic encoder ring magnets