Spectrum Full-Aperture Glass Solar Filter 4.00" ID – ST400G

Spectrum Full-Aperture Glass Solar Filter 4.00" ID – ST400G is designed for safe, full-aperture solar observation through compatible telescopes. The premium glass filter helps produce a natural yellow-orange solar image for viewing sunspots, eclipse phases, and solar detail.

• Full-aperture glass solar filter
• Aluminum cell with nylon thumb screw and felt padding
• Designed to slip over the front of the optical tube
• Use the filter ID / internal diameter to select the correct fit

Fit note: Measure the outside diameter of your telescope tube and order the next larger filter size for a secure fit.