This is the G063345400 model from Qioptiq Photonics, a 22.4 mm diameter UVFS mounted double-concave lens with an effective focal length (EFL) of -30mm. The lens is designed with a base shape of a circle and features a spherical geometry. The center thickness of the lens is 1.5mm.
The lens's inner and outer radii are both zero, while the first and second radii (R1 and R2) are -30.287mm and 30.287mm respectively, indicating the double-concave nature of the lens.
The lens is made from UVFS material with the ID 1965. It is designed to operate at a wavelength of 355nm and comes with a coating of Qio Silver RAGV 45 on both the front and back surfaces.
The lens is currently in stock and available for purchase on the Qioptiq Photonics website. For more information, you can refer to the provided weblink.