[Paddlewise] Magnetic switches

I've got a couple of backup ACR flashlight/strobe combinations which are activated by some sort of magnetic rotary switch on a bezel outside the unit.  Seem pretty simple, and would seem like a good option to activate a battery powered bilge pump.

Anyone have any experience with anything like this for a waterproof switch application on a kayak?  Any resources for switches like these which would avoid deck penetration?

Jack
***************************************************************************
PaddleWise Paddling Mailing List - All postings copyright the author and not
to be reproduced outside PaddleWise without author's permission
Submissions:     paddlewise_at_lists.intelenet.net
Subscriptions:   paddlewise-request_at_lists.intelenet.net
Website:         http://www.paddlewise.net/
***************************************************************************