Fenceman energiser dp3508 the fenceman energiser dp350b has an adjustable pulse rate and can be powered by either 4d cell batteries or an external 12v rechargeable battery it will power up to 35km on 12v 1km on 6v and the pulse rate is fully adjustable from 20 pulses per minute to 60 although 40 is the norm 4 x d cell batteries are included free to get you started the d cell batteries can be slotted in to the energiser housing and the 12v battery can be attached by the two connection l