Freewell 58 mm base ring with lid for Real Locking VNDFreewell 58 mm base ring with lid for Real Locking VND The Freewell 58mm base ring is an essential part of the Real Locking VND CPL system, which allows you to securely and quickly mount filters to your lens. Made of precision milled aluminum, it provides a solid mount and compatibility with the rest of the system from VND filters to caps. The 58mm model fits lenses with such a thread and allows the system to be extended to smaller diameters. Cover