Astrozap Flexi-Heat Dew Shield with Two Notches - 11" CGE SCT & HD AZ-812-N-2 Fits 314mm dia. Optical tubes Two notches for upper & lower bars The Astrozap Flexible Heated Dew Shield uniquely combines both active and passive methods of dew fighting with the added feature of shielding the telescope from undesirable stray light. Felt-lined to help absorb moisture and to prevent extraneous light from reaching the optics and greatly improving contrast. Proudly manufactured in the USA!