In anticipation of a GC or Cataract trip I bought a 12V wireless remote control that I had planned to secure on my oar just below the handle. or on my PFD. This would allow me to engage the pumps only when needed (sometimes a little water in the boat helps with punching holes) instead of a mercury switch or float bouncing around and nuisance click-clacking the pumps from rapids turbulence.
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This isn't the exact model but similar, I bought 3 (2 fobs each) for about $15.00 each.