Towards the right hand side of the unit is the grey swing out handle which serves two purposes on this unit. The first is to lock and unlock the aluminium hard drive chassis into place when the unit has been installed inside the plastic housing. The second is to shield the key lock which acts as a deterrent should anyone consider attempting to remove the hard drive when this unit is in operation. The key lock has three status segments which describe what mode the MB452UK-BK is operating in. When the key lock has been turned to the "A" position this means that the power status is "ON" and the system is in locked mode. When the key lock has been turned to the "B" position this means that the power status is off and the system is in locked mode. Finally, when the key lock is has been turned to the "C" position this means that the power status is "OFF" and the unit can be removed. On the left and right hand sides of the plastic housing, Icy Dock has added aluminum mesh filters which assist with air circulation and cooling.