Lomography Monocle lens 28mm based on  industar-61  lens  M39 mirrorless cameras
It can be adapted for deferent  mirrorless cameras.
Tested on camera and works well . 
Caps included. 

A monocle is the simplest soft-focus lens using only one lens. The monocle produces a characteristic soft pattern, allowing you to obtain an image with reduced contrasts and spherical aberration, which gives a “glow” to bright objects against a dark background.
The monocle is applicable in a huge number of photography genres and is practically unlimited. Becoming the basis for modern Pictorial photography. However, it is partly possible to identify the main areas of use where the validity of the Monocle pattern is undeniable.
1. Portrait is the main aspect of the Monocle, its soft drawing allows you to get rid of excessive detail, and is especially impressive in a facial portrait. (photo-1.)
2. Landscape photography, in which the Monocle is most often used to obtain “effects” that are excellent in backlight.
3. Still life is also not a problem for a monocle; its design gives the image airiness and richness, and glass objects look simply amazing.

Serial number can be another
Sony camera on photo not included show as example installation.