This item includes three tools for collimating a Newtonian reflector having an 1 ¼” diameter focuser:
• A sight tube having centered crosshair wires. This is sometimes called a peep tube.
• A Cheshire eyepiece. This has an opening on the side for providing illumination.
• An autocollimator eyepiece.
This also includes the instruction book shown in the photo.
The eyepieces and instruction booklet were bought as a package, so the booklet references exactly those eyepieces.
I don’t use these any longer, but I’m offering them at a low price (that includes shipping!) for someone who wants to learn how to collimate a Newtonian reflector.