Small front lens elements are typical of macro lenses.
You can get very impressive enlargement of small objects using a
macro lens.

Specification:
20HC 1/2” Manual Iris Lens
Mount: C-mount lens
Focal length :25.0mm
F-stop: F 1.6-16
Angle of view: 14.6°H
Size: Dia30.5x25.5mm.