Countermark

https://rpc.ashmus.ox.ac.uk/countermark/779 
GIC 654
monogram PHILP
square 
3.5 mm 
GIC gave PHR as the monogram with Phr(ygia)? Applied at Philippi not certain 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC I, 1656 Show 1656 63 1
RPC I, 1657 Show 1657 21 1
RPC I, 1659 Show 1659 6 1
RPC I, 1656 Show 1656 127 1
RPC I, 1656 Show 1656 89 1
RPC I, 1656 Show 1656 132 1