From the Dixon Inventor Series
This combines the Magnetic Drop Clutch with the Trip Arm.
Lets your hi-hats operate normally when the clutch is engaged, but when you gently strike the disk, the clutch will pivot and the cymbal top will drop. The cymbals are closed so you dont need to keep your foot on the pedal. Step on the pedal and the clutch will re-engage and the hi-hats will operate normally again.