ARMO has recently released a new series of kits of German AA guns. The other kits include turned aluminum (or brass) gun barrels, but this current kit is all resin. For the most part, the molding quality is outstanding, with the exception of the gun barrel, which is warped in two different directions. It will need replacing, and luckily, there are metal barrels available now from several companies, including ARMO.
As you can see in the scan, the number of parts is extensive. This is a highly detailed kit, and I am extremely impressed. And here is the kicker: it actually comes with VERY GOOD instructions. A first for ARMO. I can highly recommend this gun, but only if you get a sample with a straight gun barrel.
By the way, this is the version of the 37mm Flak which was mounted on the Sd.Kfz. 7 half-track, so it will make an excellent replacement for the fairly poor gun which comes in the Hasegawa Sd.Kfz. 7/2 kit, which is what I plan to do with mine.
Postscript: There have been some changes in the ARMO catalog. Apparently, kit #72070 (formerly this kit) now belongs to a Horch Kfz. 15. This Flak 37 is now listed as #72075, and it also now comes with a turned aluminum gun barrel.