Griffin PowerMate Multimedia Control Knob for USB Computers, Black - Assignable USB multimedia controller. {link removed}

Description It spins like a knob. It clicks like a mouse. But it's so much more. PowerMate Bluetooth is the wireless programmable controller that replaces extra keystrokes with a simple twist or a click. It scrolls. It scrubs. It clicks like a mouse. And it's user-configurable, so it can control practically any Mac application out there. PowerMate Bluetooth connects to your compatible Mac wirelessly via Bluetooth 4.0, so there are no messy wires to get in the way. Once connected, use the included PowerMate app to add your own actions and replace an app's repetitive keyboard commands. And if you already use a corded PowerMate, PowerMate Bluetooth works just fine alongside its older sibling. Does Almost Everything Better, Faster, Smoother Right out of the box, PowerMate Bluetooth is ready to handle your Mac's volume and track control. A new, totally redesigned PowerMate configuration app makes it quick and easy to program PowerMate to do so much more: Shuttle through music or movies Scroll through long spreadsheets or text files Pan and zoom in your creative applications Resize and reconfigure tools and brushes in illustration and photo re-touching programs Use multiple PowerMate Bluetooth units and assign specific functions to each Power Requirement: Two (2) AAA batteries, included For Mac OS 10.9 -10.12 Compatible Mac laptop or desktop supporting Bluetooth 4.0 protocol, including: Mid-2011 Macbook Air or newer Mid-2012 Macbook Pro or newer Late 2012 iMac or newer Mid-2011 Mac mini or newer 2013 Mac Pro or newer