TriSquare XRS TSX300 two way radio. I have tested four radios in the simplest of configurations and all have problems with loosing track of one another or lagging connect times upward to eight seconds. UPDATE: TriSquare has informed us that because of the packaging, these radios were several years old . This may explain the dead batteries and the sync problems. They have offered to send replacements so we can re-evaluate their performance. Stay tuned.