Mega-sonic Cat & Dog Repeller Defenders Mega. Sonic Cat & Dog Repeller Twin speaker unit maximises dB output and coverage area to deter cats, dogs and foxes|Motion activated sensor detects animal movement and activates sonic output (coverage 200m)|Push button testing with LED activation|Adjustable stand height and ground anchor|Battery or mains powered using 9v Universal Mains Adaptor (STV612)