DORHEA 12PCS MG90S Servo Micro 180° 9G Servo Motor Geared Micro Servo Motor 9G Smart Robot Compatible with Raspberry Pi Project Car Helicopter Airplane Boat (180 Rotating)

Working well

Arrived well packed and work as they should, good deal and would recommend and also would buy again

Used these in a ground based (thankfully) project. 12 servos. 4 plugged into the board overloaded the 3 amp buck converter at an idle. Found some the pulled too many amps. A few completely dead. Some get hot. All are extremely weak. Your milage may vary, but there is no way i would purchase these again for any purpose let alone in a flight application. Of the 12, 5 are still in project. They are getting cycled out as i write this. Consider Miuzei instead. So far they are working smoother. On teardown they are not even MG90 servos. All gears are plastic but the one you see on the outside.

Let's just address the obvious issue on these servos..... I believe that most folks purchase these with the assumption that it is a metal geared servo.... it's not. The only metal gear is on the output, the rest are gray plastic (you can see in the picture that I included). If you need these for a project that will put stress on the servo, do not use these. I had these in a delta wing RC plane and stripped 2 of them out just belly-landing into grass (no huge impact, just landed and the servos started making the classic whirring noise).For the price, they are adequate. You can't expect much out of a servo that costs $2.70 a piece. I have been using these in lightweight, foamie RC planes and they get the job done. However, any sort of hard landing or crash has stripped out at least one servo. I would not use these in anything that has higher value. They are pretty quick and have decent torque for their size. The output will rotate 180 degrees by hand, but I could not get them to go more than 90 degrees when hooked up to power.I've ordered 3 batches of these servos and at least 10% of them didn't work right out of the box. I managed to fix them by resoldering the wires (it's a tiny spot and not easy to do).Overall, these work great for cheap-o RC planes that won't be flying fast or high. They still get 3 stars in my book because they're very inexpensive and they do work..... they just aren't true metal-geared servos.

The final drive gear is metal but the other gears are not. the gear on the motor shaft will come off if it gets in a bind. The motor gear is not metal nor is the center gears. These will be fine for light duty projects, just check that they will handle your project.