It's no surprise that the Aegis Rat Bait Station's double-tunnel design improved rodenticide consumption by up to 57% over other bait stations on the market. Rats are more likely to enter the tunnels of Aegis Rat Stations, which are made of heavy-duty polypropylene. Uniquely patented, double-quartered locking barbs make the Aegis tamper resistant. Use indoors or outdoors in any type of environment (commercial, residential, industrial and agricultural).