Package arrived several weeks well within the stated time period. Works exactly as specified. Have used it to control a hard disk drive that I've re-purposed as a grinder (see Youtube example hacks), which works great: finally found something useful for old hard drives :)
The trick with this controller is that you need to configure it differently depending it it's a 3-wire motor or a 4-wire motor, as per the diagram on the Banggood page. The package comes with the two connectors ("shorting caps" shown on the diagram) that need to be mounted differently depending of the wiring type - again, refer to the diagram to see the configuration. Lastly, the potentiometer to control speed works smoothly with a wide range of speed from from 0 RPM to maximum.
Photo of my "hack".

Bonjour,
Je tenais à vous remercier pour cette envoie de qualiter.

Tout est au Top, je recommande le Marchand à 100%
5 Etoiles facile.

Merci, à bientôt :)