The supplementary lens is either part of the main lens or housed in the handle. Its diameter is significantly smaller than the diameter of the main lens. The supplementary lens provides additional magnification.
Levenhuk
Magnifying glass Zeno Read ZR10 White 80mm 2x / 6x
$ 11.90
ready for shipping in 1-2
weeks
TFA
Magnifying glass Handheld magnifier 84mm 2x / 4x
$ 15.90
Sale price:
$ 11.03
ready for shipping in 24
h