This is a Plano-Concave lens, type of spherical lens, sourced from CeNing Optics. The lens has a base shape of a circle and a diameter of 25.4 mm. The lens's center thickness is 2 mm, and it has an effective focal length (EFL) of -75 mm, making it a negative lens. The inner radius of the lens is 0 mm, and the outer radius is also 0 mm, indicating a plano surface.
The lens is made of N-BK7, a popular optical glass from Schott, known for its excellent optical properties and wide transparency range. The lens is designed to work at a wavelength of 546.1 nm. It does not have any coating specified, which means it is uncoated.
The lens is in stock and available for purchase. For more information, you can visit the vendor's website through the provided link.