They are not a part that is sold separately as the watches are not intended to be user serviceable. The only way to get the watch properly sealed again is too send it into a Polar Authorized Service Center and have them replace the seals/ Batteries. The seal/ gasket is a pressure seal, so when they put the new one in they also use a special vacuum sealer to make it water tight. Send the watch in and they will fix it up right for you, plus you get a warranty on the service work they do, very helpful if something goes wrong.
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...jkexer polar 5090 treadmill and its coming up E1 any ideas please 1) You must adjut the speed sensor, clean it, tight the connector very well.see the ...
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