Worm Gear Gearbox NMRV-030 Speed Reducer Ratio 10 :1 for Stepper Motor

Almost zero backlash. at 12" off the center, maybe can get about 0.5 mm freeplay. close to the hub can't detect any. Comes with non vented oil plug installed and extra vented plug included.

Works for my application. I am pleased with the power transfer of the box and the price was reasonable.

I ordered three of these for a project. Amazon fulfillment, so shipping was fast and they were pretty much as advertised. Only irritating part is the mounting screws for mounting the reducer to whatever (I.e. not the motor mounting holes, but the other set of holes around the output shaft on both faces) are M6x1, not M5. Seems strange that they would opt for a different thread but keep the hole spacing the same as the Nema 23 flange. Still, they didn't specify those holes that I could find in the images and product description, so it isn't like they didn't deliver as-specified, they simply failed to specify. Buyers might consider it worth their time to inspect prior to planning your installation so you don't select the wrong fasteners (or the factory has no spec for those holes and you get whatever you get).

Its pretty amazing that you can buy a high quality worm reducer for this little money. I think the quality is better than the original manufacturer. I adapted it directly to the linear slide I bought from the same company to use for an elevator. I was very impressed.

This gear box is perfect for my welding turntable. The gear ratio is 80:1 it's nice compact and light.

What kind of oil does the gearbox need?

Plan your projects carefully. I ordered this to step up a water wheel to produce electricity. While it may yet prove viable, size is ridiculously small. I am not sure it will handle the torque due to size.Previous photos make it appear much larger, honestly surprised it is 1/4 the size of my 3:1 gearbox.

What I dislike it came to small I needed a bigger gear. They should specify very clear the size in inches. Thanks