This is a discontinued product. We suggest the Farpoint Flexible Dew Shield as a replacement.
This model is compatible with all 14" optical tubes.
A Lens Shade/Dew Cap is a tube, of approximately the same diameter as your telescope tube, designed to fit on the front end of the telescope to reduce the amount of dew that builds up on the corrector plate. It also serves as a Len Shade by preventing stray light from falling on the corrector plate, which greatly improves contrast.
Celestron also offers a complete line of rugged, but soft Foamex plastic lens shades that can be put away flat after usage. They use a thicker material and won't crack easily as other manufacturer's products do. The quality level is a step above all others as all material is sewn (not glued in some places) for a long life.