Buyers Products K90 Series Power Take Off/Hoist Control Valve Operates Pneumatic Truck Functions With The Simplicity Of A Single Lever. It'S Built To Perform With A Design That Allows For Controlled Lowering (Feathering) And Smoother Operation. Built-In Safety Features Vary By Style And Help Reduce Operator Error. All Valves Have A Control Pad Indicator Light That Warns Of Pto Engagement. The K90 Has Automatic Disengagement Of The Pto In Lower Setting, While The K90D Has A Dead Man Control On The Hoist Lever, Which Returns To Neutral Position And Stops Motion When User Engagement Is Not Present.