Countermark

https://rpc.ashmus.ox.ac.uk/countermark/495 
GIC 375
axe, double-headed with serpent around handle
On reverse 

Coins with this countermark

Number Image TypeNumber CoinNumber VolumeNumber
RPC II, 1386 Show 1386 3 2
RPC II, 1386 Show 1386 9 2
RPC II, 1386 Show 1386 14 2
RPC II, 1386 Show 1386 17 2
RPC II, 1387 Show 1387 7 2