How much does this cost to the nearest dollar?

Sonim XP5s XP5800 4G LTE Military Grade, Single-SIM, Rugged PTT Feature Phone, 16GB, 2GB RAM, (Black) - AT&T Unlocked
What does gsm unlocked really mean Unlocked devices are compatible with GSM carriers ONLY. I.E. Networks that Use SIM Cards for Service like AT&T and T-Mobile, as well as select prepaid GSM SIM cards (Cricket, H20, Straight Talk, Wal-Mart Family Mobile, Unlocked Devices will not work with CDMA Carriers, The kinds that don't use sim cards for service like Sprint, Verizon, Boost or Virgin. Hardware specs Battery Size is removable Li-ion which on standby lasts up to 11 days as well as 19 hours of talk time, This

Price is $180.00
Price: $179.99