Postage free military cover (handwritten "F.M." = Franchise Militaire) from BP.315*21.5.18" via "BP.999*24.5.18" to France. Serbian censor cachet "30" (type IV/A) in lilac and French tape "CONTROLE POSTAL MILITAIRE", cachets "CONTROLE/2" and triangular "N.O". Handwritten "T 0.50" postage to be collected.