A telescope finderscope a small telescope attached to the main telescope optical tube assembly. It is of low power with a wide field of view and assists you in pointing to find objects to observe through the main telescope. Crosshairs aid in centering the object you seek. Most finderscopes give an inverted (upside down and left/right reversed) image.
Typical finderscopes come in 6×30, 8×50 or 9×50