Acxico 10Pcs DC 5V 2-Phase 4-Wire Micro Mini Ultra-Tiny 4mm Precision Small Electric Stepper Motor Small Motor DIY

They do work - The support posts are plastic so be very carefull when soldering tiny wires to the connectors, otherwise you risk melting the post or breakingh the small coil wires - Ended up connecting with 0.1mm magnetic wire - Seems to be about 18 Steps per revolution - run very hot. Tested with DRV8833 drivers (no current limiting resistor) : These Steppers are rated @ 5A / 300ma

I ordered 4 packs of 10 for a total of 40 motors. Nice and small for 1:87 (HO) scale models. In order to drive these I will connect them to an L293D or an DRV8411A chip which are H-Bridge motor drivers. Soldering these will require experience and diligence as noted by the seller. A soldering iron held on the wire posts too long and/or too hot will easily burn the extremely small wires. I will probably end up destroying a few before i get a good connection. Well worth the cost if you can solder this small with extreme care. Definitely recommend these but order more than what you need because you will probably damage a few before you get them working.

simple fun

Soldered up first try. Running on TB6612 driver at 5V - getting EXTREMELY hot to the touch while suspended in air.

Got device working but simply was not strong enough for my purpose on an N-scale railroad project. I may find another use for them elsewhere on the layout.