I have two choke tubes here marked F(1,0). Assume that means Full, 1 mm. But I don't know what gun they are for. They have two slots for the key and a one little nick (code for full I suppose). They look similar to Browning but I don't think they are. Anyone know? If so pls email me.

Looks like Full all right. Not Browning though, as these are etched with Browning brand and equivalence lead/steel. Might be Winchester or Miroku (if they fit a Browning gun) as both are owned by Browning.

they have very fine threads and no, they don't fit the Browning Invector system

your chokes are maybe Mossberg, could be wrong???. The early chokes where 1 1/2" long. They fit mossberg, win. early browning citories. The 2 notches for the choke wrench was Mossberg. The F means full choke, when used with certain ammo types, the 0 means full choke with 0 size buck shot. The 1 means steel shot for geese. The one little nick means Full choke. The newer choke tubes are longer. 12ga info here

They are 1.605" long. I have some Mossberg chokes as well, those have two bands around the choke near the mouth. These have no bands. 1,0 is possibly 1.0 mm (they use commas in Europe instead of the decimal point), ie 40 thou of an inch, which would be full.