AUDIO TECHNICA 251 WIRELESS WITH PROVIDER SERIES HEAD-CLIP AND PSL6 LAV. Audio-Technica’s Freeway® 200 Series Wireless Systems are designed to provide reliable performance, easy setup and clear, natural sound quality. Available in handheld, headworn, guitar, lavalier and body-pack configurations, the 200 Series Freeway Wireless Systems are single-channel, fixed-frequency systems available in three VHF frequencies (169.505, 170.245, and 171.905 MHz).