[2014 New Version] Esky Reachargeable LED Digital Display In-ground Dog Shock Collar Electric Fence System (Two Collars) Rechargeable transmitter with LED digital display, ease for training or operation Rechargeable and water-resistant receiver-collar; No extra battery is required Premium quality 18 gauge (1mm) copper boundary wire; Compared with the ordinary 22 gauge (0.6mm) tinned copper boundary wire in the market, ours will be more durable and improve performances in all aspects. The signal can cover up to 2500 square meters range area. (Over 0.62 acre) Proportionally Increasing Static Shock