The #17816 3-inch Adjustable Extender Tube adds anywhere from one to three inches of back-focus to your optical setup by making use of V-grooves that are set at multiple points along the body of the tube. The back of the tube presents an OPTEC-3000 dovetail to attach to any product with an OPTEC-3000 receiver, including the TCF-S3, IFW-3, and Pyxis 3" rotator.

Specifications

• Outside Diameter: 3.56" (90.4mm)
• Overall Height: 4.5" (114.3mm)
• Clear Aperture: 2.65" (67.3mm)
• Weight: 12.48 oz (353.8 g)
• Back-focus Usage: 1-3.1" adjustable (25.4-78.7mm)
• Telescope Side Connection: 3" Adjustable V Groove
• Camera Side Connection:: OPTEC-3000 Receiver