Open Box display model. This is an early model FLT91 in red used as our display model.

Red anodizing shows slight weathering from being out on display. Few minor nicks on the finish as shown in photos. Clean optics. A great opportunity to save big on a quality optic! 

Features

• 91mm APO Triplet for tack-sharp stars
• 3.3" heavy duty dual-speed focuser can handle the heaviest imaging loads
• Rotolock system for 2" diagonal
• Refined anodized aluminum finishing
• Included 2" extension tube for close focus or camera connection (if you can't reach focus, remove the 2" extension tube when used with a 2" diagonal and eyepiece or with cameras and flatteners.)

A precision-engineered apochromatic triplet refractor designed for discerning astronomers and astrophotographers. This mid-sized telescope features a 91mm aperture with FPL-53 glass, delivering sharp, high-contrast images and an impressive Strehl ratio exceeding 0.95.

Equipped with user-centric features, the FLT91 includes an integrated saddle handle, a 360º field rotator, a dual-speed 3.3" Rack & Pinion focuser, and a 2" Rotolock system. These enhance usability and provide stability for both visual and photographic applications.

Astrophotographers will find the built-in Bahtinov mask invaluable for achieving perfect focus effortlessly. Compatible with the Flat 6AIII, Flat 68III, and Ultra Flat 91, the FLT91 allows precise back-focus adjustments.

Constructed with William Optics' signature quality, the FLT91 is both lightweight and durable, weighing 4.2 kg and 5.6 kg fully equipped. It comes with a soft carry case for easy transportation and protection.

Ideal for capturing celestial phenomena, the William Optics FLT91 is a top choice for those seeking advanced optical performance in a portable package.

Example Images

Diagram Reports

Specifications

Online Manual