AstroZap Full Aperture Aluminum Bahtinov Focus Mask for 14.5" - 17.5" OD Telescopes - AZ505

The Astrozap AZ505 is a full-aperture aluminum Bahtinov focus mask designed for telescopes with 14.5" to 17.5" outer diameter tubes. This lightweight, thinly-designed mask utilizes the proven Bahtinov diffraction pattern to provide precise, intuitive focus for both visual observing and astrophotography. The solid-sheet aluminum construction with powder-coat protection offers superior durability compared to plastic alternatives, and the adjustable rubber grommets with plastic screws secure the mask safely to your telescope without damage. Ideal for achieving sharp focus on large-aperture telescopes, the AZ505 simplifies the critical focusing process for both visual observers switching eyepieces and astrophotographers capturing deep-sky images.