This unique tool eliminates forever the need for making your own electrical tester. Constructed with two sharp needles and a self-contained light bulb, the HW2229 Test Probe can be used at any point along a conductive tape run for electrical testing or finding a tape run under wallpaper. Simply push the needles into the copper strips and, if electricity is present, the enclosed bulb will light. The .175" pin spacing makes this handy tool useable with any tape system. It also provides proper spacing for placement of the eyelets when installing the CK801 Sconce Adapter or the CK804 series of Chandelier Adapters. Comes with snap top safety cap. Overall length approximately 2". Dimensions: 2"L x 3/4"W x 1/4"T. This is sized for a dollhouse. Detailed scale model for adult collectors. Not intended for children under 14