DP2000, DP2400, DP2600, DP3441, DP2000e, DP2400e, DP2600e, DP3441e, DP3661e. Arrowmax APM100-AX Light Duty Shoulder Mic Speaker Microphone for MOTOTRBO DEP550 DEP570 DP2000 DP2400 DP2600 XPR3500e. It is made slightly smaller than palm-size.
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