Per the owner they are chinese spindles made by GPenny, i guess to his specifications.

Spindle motors can be induction-type (a.k.a., asynchronous) or synchronous-type.

Consider the specific cutting requirements of your application. Higher torque allows for more efficient material removal, especially when working with tougher materials or using larger cutting tools. Choosing a spindle motor with sufficient torque is essential to effectively handle your specific machining tasks.

Unlike routers, you don't use spindles by hand or on a CNC machine. Because of this, they don't typically have a plunge base on them or a dust extractor. Instead, they normally consist of the spindle itself and the motor. Spindles generally have one of two types of motors: an electric or air-powered motor.