This is a electric fence energiser that is also compatible for mains usage or 12 v battery usage. This is useful if you need to fence a outfarm and this energiser can be moved easily.
 
Specifiactions:
 
12v battery
220v mains
1 output Joule
12v 40Ah battery life 2/3 weeks
Can fence up to 25 acres/ 5 miles (8km)
Suppied with adaptor