The Seestar is a great telescope and is ready to use right out of the box, but adding a couple of key items can really improve the experience. A dew shield is one of those key items. It's true that the Seestar has a dew heater, but that uses the battery and reduces your imaging time. On some heavy dew nights, the built-in heater just isn't enough to keep up. Adding the dew shield is a huge improvement. In addition to reducing dew, this also blocks stray light from entering the scope and improves the image quality when used in areas with stray light. This lens cover is specifically designed to fit the Seestar S50. 3D printed from ultra durable matte-black PETG, this is a huge improvement in durability over the more common PLA material. PETG is much more temperature and impact resistant than PLA.