Releasable locking and sealing assembly

A releasable locking and sealing assembly comprising:

• in a linear motion potentiometer;
• an elongate body having cylindrical end portions, said end portions having an annular recess;
• an O-ring disposed in each of said annular recesses formed from a stiffly deformable, springy material having a cross sectional diameter greater than the depth of said annular recess;
• a hollow cylindrical casing it fit slidably over said elongate body having an inner diameter at least as great as the outer diameter of said cylindrical end portion but less than the principal diameter of said O-ring compressing said O-ring to between about 70% and 85% of the cross-sectional O-ring diameter;
• and
• truncated annular grooves around the interior of said cylindrical casing spaced from each end thereof and adapted to be aligned with said O-ring disposed in each of said annular recesses, each of said annular grooves having lips formed from the edges of said truncated annular grooves defining a groove width of from about 25% to 50% of said cross-sectional diameter of said O-ring forming a bead from said stiffly, deformable, springy O-ring material between said lips within said annular grooves.