Custom 3D-Printed Dew Shield for Vaonis Vespera Series Telescopes - Auto Folding & Stowable This essential dew shield prevents dew formation around the lens and blocks stray light from nearby sources. Its design allows the telescope arm to operate freely, as the dew shield auto-folds when the arm closes. The dew shield has an adjustable collar that is put on the telescope arm and locked using inbuilt clip. The dew shield can also be stowed in the telescope arm itself when not in use for easy transport. I use this dew shield regularly with my Vespera and have never encountered dew, even on the filter. It's recommended to use it with a hygrometer that heats the lens in cold weather. What is in the box: Dew Sheild Tube Adjustable collar