College grade (concave or convex) highly silvered, optically true, special quality, F.L. 10, 15, 20, 25 cm
Diameter : A. 50 mm
B. 75 mm

In metallic frame, richly chromium plated with handle
A. 37 mm
B. 50 mm FL-20
C. 75 mm FL-20
D. 75 mm FL-30
E. 100 mm FL-20

For refraction experiments, moulded block, all sides polished, edges slightly bevelled, 75 x 50 x 18 mm
A. Indian Glass
B. English Glass

32x32 mm
A. Extra Dense Flint Glass
B. Dense Flint Glass
C. Crown Glass

1st quality, equilateral or right angled, bubble free, non-optically worked, with polished faces
A. size 37 mm
B. size 50 mm

Special quality, equilateral or right angled
A. size 37 mm
B. size 50 mm

Uniformly moulded and well edged
A. 50 mm
B. 75 mm
C. 100 mm

Ground glass, well edged size 75 mm

75 x 25 x 2 mm nicely polished, with ground edges, in pack of :
A. 50 slides

18 mm superior quality in 10 gm pack
A. Round
B. Square