Glass fresnel lenses in borosilicate glass. Large fresnel structure on the front face with a slightly textured rear surface to allow some diffusion of the light pattern. These lenses are available in various sizes as follows:
| Diameter | Effective Focal Length |
| 50mm | 30mm |
| 80mm | 40mm |
| 130mm | 100mm |
| 150mm | 120mm |
