An electronic device 28 with an effective water sealing button system 26 comprising a special compression gasket seal with compressive faces 30 and 32 and deformable annular seal portions 34 and 36 to dynamically seal a moveable side key 20 providing a button 22 against a housing 40 of the electronic device and accommodate non-binding sliding movement of the side key while controlling the spacing and tactile feel of the side key.