The Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH MFT is a versatile zoom lens for Panasonic's Micro Four Third cameras made with Leica's high quality optics. With its zoom range between a standard zoom and a telephoto zoom, this lens is perfect for shooting portraits and product photos. It has an F1.7 aperture opening across the entire zoom range and thus performs well in low light. The lens also features a clickless aperture ring thus perfect for smooth, silent control of the aperture during shooting. 

Additionally, this lense perfectly matches its big brother the Panasonic Leica DG 10-25mm f/1.7 ASPH which has a very similar design. Therefore, it is easy to swap those two lenses when in use with a rig without having to do any modifications, which gives a lot of possibilities for filming and photographing. 

Finally the dimensions of the lens are 127.6 x 87.6mm, it has a filter thread of 77mm and it weighs 654 kg.