The JMI Event Horizon EV-3RM is a 2" black-anodized aluminum focuser with silver anodized knobs, and single-speed operation. The focuser lifts up to 4 pounds. Single-speed manual control is over 1.5 times finer than most rack-and-pinion focusers.
The EV-3RM mounts in many refractors having one of two different inside diameters of approximately 3.5" and 3.75". The focuser is motorized, so focusing is done with a touch of a button on the included hand control unit. Manual control with the knobs is still possible without removing the motor.
Partial list of Refractor Telescopes that should accept the focuser: