French naval post?, 9 letters
THREE ROOMS, 15 letters
*Secret communication location, 8 letters
Courier's stop, 8 letters
Cubbyhole in an office, 8 letters
Forwarding service provider, 8 letters
Letter slot, 8 letters
Office distribution unit, 8 letters
Place for a pickup, 8 letters
Postal receptacle, 8 letters
Spy's address, 8 letters
A drop where mail can be deposited, 8 letters