* a jigger is also known as a battery, harp or jack

* usually a small electrical device used in conjunction with a whip to try to stimulate a horse to run faster

* used in trackwork then on race day an action is simulated so the animal believes its about to be shocked again

* may be used in conjunction with a gear change such as blinkers. The blinkers are used in trackwork in unison with a whip and an electrical device, come race time animal believes it will be be shocked again when struck with whip

* it is against the rules of racing for trainers, jockeys and stable staff to be in possession of such electrical devices

* trainer Darren Weir faces three charges of possession of an electronic apparatus capable of affecting the performance of a horse and Jarrod McLean one charge

* in 2007 Victorian trainer Paul Preusker (four years) and jockey Holly McKechnie (three years) were banned for using an electrical device on a horse during trackwork

* track rider Damien Bradbury was disqualified in 2015 for 18 months after pleading guilty to possessing an electrical device at Mornington

* Kembla Grange trainer Shane Kember banned in March 2014 (15 months) for possession of an unapproved wire whip covered in electrical tape