This is the KG-1245 kit consisting of the KG-867 Edge Guide and the KB-09 adapter bracket. The kit is designed for use on Pfaff 1245 and Pfaff 335 sewing machines.
The kit can also be used to retrofit vintage machines (see last picture for an example of a Singer 111/Consew 225 installation), but may require drilling and tapping suitable holes.
The kit items are available separately as well in my other store listings.
Order this kit (as opposed to individual kit items) if your are located outside the U.S. - it will lower the shipping bill for Ebay Global Shipping.
I replaced the standard M5 screws in this kit with special flat head screws. This eliminates the need to cut the rear cover on modern casting Pfaff 335/1245. The special screws do not affect installation on other machines.
Installation video on a Pfaff 335: