This sheet is intended for use with the Wings Of War Ryrie and Baker Sopwith Snipe models, and provides individual aircraft codes and large ID letters / numbers for 4th AFC when they were issued the Snipe in the final couple of months of WWI.
The sheet includes ID letters for the entire squadron (A flight A-G, B flight 1-8 and C flight S to Z, as well as I and J which were probably squadron spares.) As well as that it it has the correct serial numbers for every Snipe issued to the squadron in WWI, squadron markings (white bar forward of the roundel) and a few sets of roundels if you decide to go for a repaint.
Finally you'll also be emailed an instruction sheet showing painted example models, details of where the markings were applied (including a couple of corrections to the existing markings on the WoW models) and a list of as many matches between aircraft code and serial number as I've been able to figure. (This latter has been extensively researched from a variety of sources.)