Now a special order item due to the costs of the socapex shells and the small numbers of orders of these items - please email if you are wanting to buy one... Socapex Tester Continuity model. For testing Continuity through bulbs from live to neutral and shows earth faults. Often used in conjunction with loop-back tester to test soca cables. Please also note that the tester for sale does not match the photo as now using a block of 10 led's instead.