found at DigiDirect
Key Features:
Allows a full frame Rollei QBM lens to be mounted to a Micro Four Thirds mount camera and in doing so, increases the angle of view and increases the maximum aperture one f/stop.
Precise fit and solid connection
The exterior features a black satin surface finish.
A built-in clickless aperture control ring enables manual control of aperture from the speed booster. This 8-stop ring with clearly marked 1/2-stop markings is shipped as clickless but can be converted to clicked with the included click ball and spring.
The speed booster is compatible with NIKKOR F mount and F Mount G lenses including AI and non-AI mounts.
Designed to reach infinity focus.
Although the lens will fit physically, automatic diaphragm (AE metering), or other auto functions are not retained using this speed booster.
Satin surface finish