LEIMO KPARTS 7-80V PWM DC Motor Speed Controller Switch 30A,Motor Speed Control Regulator

I can't speak for longevity currently, but it will work as a speed controller for a motor. I used it for my four year old's power wheels and it does change the output for the motor. If you hook your voltmeter to this, it will variate less than .5V. That's because this is a PWM and it doesn't change voltage. It changes the pulse widths for the motor. It worked just fine and was easy to install. I'll edit later for how long it lasts.

The sender did not even bother writing my complete address soo i received a call in the morning from post office asking what my address is. After opening the product i soon realised the product was very rusty both outside and the internal components visable from the gaps in the device, Not to my suprise its broke and faulty. Very disappointed. What a shame i waited soo long to get this item.

Ok

used this to modify kids electric car to use ryobi batteries instead!

After 1 month it arrived. Wited it in, it didn't work. Took the cover off and it did not have a fuse (compared pictures off product page). With a new fuse it works but the knob does not adjust voltage and the motor runs as a constant speed.