Astromania Bahtinov Mask Focusing Mask for Telescopes - FM60mm for a tube outer diameter (OD) from 65mm-100mm - can be mounted with the brass screws inside or outside the drawtube

Astromania Bahtinov Mask Focusing Mask for Telescopes - FM60mm for a Tube Outer Diameter (OD) from 65mm-100mm - can be Mounted with The Brass Screws Inside or Outside The drawtube

NEEWER USB Lens Heater, 12"/300mm Lens Warmer for DSLR Camera and Telescope, 3 Temperature Regulator Settings, Dew Heater Strip Prevents Dew, Fog & Condensation for Telescope Camera Astrophotography

Lens Warmer with Cold Flexible Cable Down to -25℃, 350mm Dew Heater Strip Prevents Lens from Dew, Fog and Condensation for Astrophotography, Lens Heater Compatible w/ Telescope and Camera in 4.26"