The Pomona 7519a twist guard Test lead set features an adjustable probe tip shroud for use in different measurement environments. By simply twisting the Test lead the user can change the exposed probe tip Length from 19mm to 4mm (0.75 in to 0.16 in); reducing both the amount of tip exposure and any chance of an Arc Flash from short circuits. The patented design offers the versatility and quality needed to instantly change your Test leads from a cat II rated probe to a cat III/IV rated probe, allowing you to meet the latest electrical safety requirements.