Here I am with my latest refractor. It seems to have been made from PVC pipe and a 50 mm lens of 1500 mm focal length. It's a singlet lens but the previous owner says it is made from some special FPL-57 glass. The eyepiece is another singlet lens of about -50 mm focal length. Altogether it gives about 30 power but the field of view is tiny beyond belief. It came with a certificate claiming it had once been owned by a famous astronomer.

Ken