1. For alignment and exact go-to and centering guide stars for photography 2. Red LED-illuminated dual-line reticle with a high-contrast 40 field of view 3. 12.5mm length and 11mm eye relief forcomfortable observing experiences 4. Fully Multi-coated optics & blackened inner wall high light transmission 5. The eyepiece is powered by 3xCell battery and the illumination is adjustable. model: -1.25-01 Size specifications: 1.25inch length: 12.5MM Field of view angle: 42 Pupil distance: 16MM Membrane system: FC Colour:Black&Silver Material:Metal Package Contents: 1 x Reticle Illuminater Eyepiece Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.