Telescope Adapter Ring, 8PCS Photography Extension Tubes Accessories M42x0.75mm Thread Specification

How to Use: 1. Remove the objective lens. 2. Connect the telephoto tube to the eyepiece and the objective lens. 3. Then connect the objective lens. Specification: Item Type: Lens Extension Tubes Material: Aluminum Alloy Color: Black Product Size: Approx.3mm / 0.12in, 5mm / 0.20in, 7mm / 0.28in, 10mm / 0.39in, 15mm / 0.59in, 20mm / 0.79in, 30mm / 1.18in, 12mm / 0.47in Application: Extend the length of the primary mirror of the astronomical telescope Extinction Treatment: Internal with extinction thread Interface Female Thread Specification: M42x0.75mm Interface Male Thread Specification: M42x0.75mm Package List: 1 x 3mm Extension Tube 1 x 5mm Extension Tube 1 x 7mm Extension Tube 1 x 10mm Extension Tube 1 x 12mm Extension Tube 1 x 15mm Extension Tube 1 x 20mm Extension Tube 1 x 30mm Extension Tube Note: 1. Please allow 1‑2in error due to manual measurement. Thanks for your understanding. 2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard.