The PB-1 three star pocket beeper affords the operator quick discernment of point-to-point continuity. As a transistor and diode tester, it analyzes in circuit junctions for go-nogo normality. It indicates leakage, shorted or open conditions of transistors.Specs amp; FeaturesContinuity, Portability, Application: Quick discernment of point-to-point continuity, Quality: , OAL: 1.5 (37.5mm), Body Width: 3 (75mm), Body Height: 4 (100mm)