The first adapters, where you wished to need a brake adapter
These adapters are special, and only the freaks of you will notice that. The PMPM+20/23mm adapter has 4 bolts, but looks tiny just like one with 2 bolts. The difference is: the normal 2 bolt adapter needs to have spherical heads and washers, which are able to compensate the small angle difference between fork and caliper. With the Extension Brakeadapter you have a solid 4 bolt mounting of your caliper, with a clean looking appearance.
And the second point is, you can mount it as a +20/40 or +23/43mm. Without extra parts.
 
Note: please check the compatability chart before ordering.
 
You can see how the adapter works here.