Features: Ideal for any size yard up to 25 acres. Each system includes 500 ft of wire. Additional 500 ft rolls are available. Deluxe UltraLight receiver collar with five levels of correction, a beep warning followed by four levels of progressive correction. Audio break alarm warns when wire has been broken. Waterproof receiver. Progressive correction Safety features include protection against false signals and extra surge protection for storm-prone areas. Easy-to-follow operation manual and video.