Reeth Company have many different diameters Bi-convex / Double Convex glass lens K9 Materials with different diopters, the detail as below

item Lens Diameter Focus Length Diopter
1 20mm 40mm 25
2 27mm 100 mm 10
3 40mm 200mm 5
4 40mm 152mm 6.5
5 40mm 100mm 10
6 40mm 50mm 20
7 44mm 66mm 15
8 50mm 300mm 3.3
9 50mm 250mm 4
10 50mm 200mm 5
11 50mm 120mm 8
12 50mm 100mm 10
13 50mm 48mm 20.8
14 62.6mm 67mm 15
15 45mm 100mm 10
16 50mm 40mm 25
17 102mm 20mm 5