Line and cross generating lenses    
Type Number Size (mm) Character
Ø 3 Length is 8mm columniform
Ø 5 Length is 8mm columniform
Ø 7 Length is 10mm columniform
R 2.5 Length is 8mm,width is 5mm square
R 3.5 Length is 10mm,width is 7mm square
R 7 Diameter is Ø10mm round
R 10 Diameter is Ø12.5mm round
R 15 Diameter is Ø10mm round
R 20 Diameter is Ø12mm round