Usongshine Stepper Motor Driver TB6600 4A 9-42V Nema 17 Stepper Motor Driver CNC Controller Single Axes Phase Hybrid Stepper Motor for CNC/42 57 86 Stepper Motor（3 pcs

No loss of steps and great price. I really like them so far.

Used to automate model railroad turntable.Very pleased that the plug-on screw terminals were separate by function: power, stepper motor, control

Very good drivers for the money. Smooth operating. Nena 23 motors. No problems so far on my CNC router

These seem to work mostly as advertised. I didn't open them up, but they seem to be TB6600 drivers as they work at the highest micro steps per rotation and the fakes don't. I'm only using them at 2.5 amps per phase. They are advertised as 4 amps per phase, but the datasheet says 3.5 amps is the max continuous output.A complaint that I had was that the screw terminals were so tight that I ended up stripping the head of one and having to buy a replacement connector, so it ended up costing me the same for 3 as if I bought 3 individual drivers.

Fake advertising! Current only goes up to 1.5A DC (suppose to be 3.5A with SW4/5/6 off). Tested all three units, all units behave the same and all deliver less current than advertised at all DIP switch settings. Internal driver has S109AFTG inscription (supposedly TB67S109AFTG part) and judging by the quality of the laser engraving and fact that it cannot deliver spec. probably points to it being a fake. Flimsy construction, the driver chip is compressed to the heatsink with the plastic frame.

1 driver was dead on arrival. Another failed shortly after I started using it.