$5
$1: http://www.ebay.com/itm/1Pcs-4-X-AA-Battery-Holder-6V-DC-Power-Case-W-9V-Clip-Black-Plastic-HM-/201384028360
$1: http://www.ebay.com/itm/5pcs-Double-ended-Test-Leads-Alligator-Crocodile-Roach-Clip-Jumper-Wire-2016-/331949160689
$1.50: http://www.ebay.com/itm/45x45MM-Tens-Machine-Replacement-Electrode-Pads-Massagers-Reusable-Adhesion-New-/371515038247
$1.50: local AA batteries
$1: http://www.ebay.com/itm/1Pcs-4-X-AA-Battery-Holder-6V-DC-Power-Case-W-9V-Clip-Black-Plastic-HM-/201384028360
$1: http://www.ebay.com/itm/5pcs-Double-ended-Test-Leads-Alligator-Crocodile-Roach-Clip-Jumper-Wire-2016-/331949160689
$1.50: http://www.ebay.com/itm/45x45MM-Tens-Machine-Replacement-Electrode-Pads-Massagers-Reusable-Adhesion-New-/371515038247
$1.50: local AA batteries