Capture speech and vocal presentation from a body-worn microphone position with a cardioid condenser lavalier configuration. The AT831CW designation identifies a compact lavalier microphone using a cardioid pickup pattern, making it suitable where the microphone needs to remain close to the talker while reducing pickup from off-axis sound compared with an omnidirectional arrangement. Its small format supports concealed or visible placement on clothing for presentation, instructional, and performance use. A TA4F connector terminates the microphone for use with compatible UniPak wireless transmitter equipment. Connector matching matters for wireless lavalier systems: the microphone connection must match the transmitter input before it can be put into service. This configuration is intended for a bodypack-based audio path, rather than direct connection to a standard XLR microphone input. The condenser microphone element also requires the appropriate powered input supplied by its compatible wireless system. Western Digital WS-AX-VX-ND-1Y-D is presented as this AT831CW lavalier microphone configuration. Its distinguishing details are the cardioid pickup pattern, condenser element, TA4F termination, and UniPak transmitter compatibility. Those attributes separate this version from lavalier microphones using other pickup patterns, connector formats, or direct-wired outputs. Select it where the existing wireless transmitter accepts a TA4F lavalier microphone connection and a cardioid body-worn microphone is required.