New Design 2021. Spencer-3D Tri Bahtinov Series 6se.
Outer Diameter =176mm
Inner Circle Diameter = 58.5mm

Tri-Bahtinov Focus Mask for Telescope - Celestron NexStar 6se.. Condition is New. Shipped with USPS First Class. Software Designed and tested. Works great with these and similar models. 3d printed and designed by Spencer 3d. As always fast USPS SHIPPING. 2 TO 3 DAY SHIPPING. BLACK . Other colors and types available just ask. Need a custom made part or mask let me know I make with no added fees for design.

SHIPPING CHARGES ARE CHANGING FOR ALL ITEMS THAT WAS ORIGINALLY FREE SHIPPING. DUE TO HIGHER PACKING MATERIALS COSTS, AND HIGHER SHIPPING COST, SHIPPING WILL BE CHARGED TO THE BUYER AND MANY LISTINGS WILL BE CHANGING OVER TO CHARGED SHIPPING. BUT THAT WILL ALSO MEAN LOWER PRICES ON THE ITEMS AS WELL. AND MORE SHIPPING OPTIONS WITH FASTER SHIPPING AVAILABLE. ALSO MORE INTERNATIONAL SHIPPING WILL BE AVAILABLE WITH MULTIPLE SHIPPING OPTIONS.