I hunted for this one for a long time. Most of the other Mikron 1's have a metallic handle, this has a Black plastic one. It looks like the same handle that is on a Busch Flexi which would indicate some collaboration between the two companies. It has Apollo Mikron embossed on the base plate (third image below) so its definitely a first generation Apollo Mikron.
This example arrived with a few issues which I document towards the bottom of the page.
There are conflicting opinions on the net, some say the middle of the 1930's and others say around 1950. If we look at the patent dates, the first patent (number DE812402) was granted on 30 August 1951, so I would be more inclined to believe the 1950 date. They were however only manufactured for a very short period.

Assuming that the handle remains attached to the head, this one breaks down into 4 pieces with the adjuster plate been one of the pieces. I've been told that the Apollo's break down into three with the middle plate been fixed to the base plate.

How does it shave.
It doesn't get much use. When I do use it, I open it about a half turn. Its fairly aggressive. With some planning, it's capable of a BBS in 1pass with some buffing.

The Repairs
When I saw it on Ebay, I thought "WOW" - Micron 1 - I do believe that I can fix it! I won it and waited eagerly for it to arrive.
The first two images below show how it arrived and when it did, it had a few issues.
1 - The first was obviously the broken handle.
2 - The second was that the twist knob held the topcap on by two turns.
3 - The Middle plate is loose.
4 - The third was (and still is) that the bottom adjustment screw is seized up.
5 - The plating has come worn through in places. All this isn't too surprising given the fact that it's about 70 years old.
Although fixing number 3 is easy, I've decided to leave it as it's easier to keep clean.
The last two..... If at some point in the future I figure out how to repair them without damaging the razor, I'll do them.

1 - The Handle Repair.
My initial intention was to have the handle 3D printed by a prototyping company, but it arrived too late in the year to do this and I wasn't patient enough to wait for the new year to use it, so decided to turn one out of nylon. The first image in the second row was the first handle that I turned for it. I found out that I definitely don't have the skills for "freehand" checkering.

Fast forward a few days, some thinking and I decided to try something else. The checkering is straight this time but the finish, although not bad, it's is not quite where I would like it. (last image of the second row)  A little more hope that I will get it right so I won't be going to the original plan just yet, simply because its more fun me doing it myself.

2 - The Thread Repair
One evening I got the idea to squeeze the top on the twist knob in a bit. Firstly - I measured the shaft of the twist knob (7.3mm).
I then took two pieces of scrap steel bar, clamped them in a vise and drilled a 5mm hole down the middle of the two pieces.
Once I had the "pilot" hole, I then took a piece of thickish cardboard, put it between the two pieces, reclamped them and drilled a 7.5mm hole. Once I removed the cardboard I had a hole of about 7.2mm.
I then took the twist knob and slowly squeezed the shaft of it, turned it a bit squeezed again. Removing and checking it frequently, until I had it where the first few threads caught the thread of the TopCap.

The images below tell the story.