Milwaukee 6116-31 4-1/2-Inch/5-Inch Small Angle Grinder with No Lock-On 12.0 Amp, 1490 MWO Motor  high overload protection and power for difficult applications Advanced Electronics - includes ESO: Electronic Shut-Off, CPT: Constant Power technology, OLP: Overload Limit Protection ESO: Electronic Shut-Off - shuts down the grinder when the wheel is stalled in a pinch providing greater control and reduced tool damage Debris Baffles  protect internal components by deflecting damaging debris out of the airflow at the intake vents Multi-Port Exhaust  reduces motor burn-up by efficiently venting hot air out of the grinder