38mm Shell Diameter 6mm Solid Shaft Rotary Encoder 3600PPR Push-pull Output 5-26V Power Supply

This is a professional quality encoder. It is quite amazing that you can get 2500ppr for such a low price in such a beautiful package. I was a little incredulous, but it did not disappoint. And a clarification here: 2500 "ppr" means "poles" per rev, not pulses per rev. That means that in quadrature, you get 10k pulses per rev. The pulses are square and clean with no noise. Rise time of 300-500ns. No random jumping at rest. Excellent repeatability.

tried this on an arduino mega on with just the a and b lines connected to the interupt pins using the digitalwritefast library to read the data coming in and it appears to work very well. I haven't tried it at the specified rpms as that's not the reason I purchased this it was not for a very precise etch a sketch either because that wouldn't be very fun after 2 minutes.

These seem like good quality, thicknesses seem right on the mark, well packed to prevent damage. Very satisfied.

The compactness of the design along with the functionality.

It has an extra "zero" output for a pulse once per turn

Very good quality and finish with everything about these encoders ,...

Worked just like described and quality comparable to encoder costing much more.

Used this encoder to test a project, I've been working on. Worked like a charm!