Personal, pen-style dosimeters clip easily to your pocket or a specific object to measure personal accumulated dose or quantity of gamma and x-ray radiation. Dosimeter is a conductive-fiber electroscope with a thin wall to allow penetration of radiation. Inside the dosimeter, the fiber moves across a predetermined scale to display the level of radiation exposure. Readings are easily displayed by holding the dosimeter up to a light source to view the scale — immediate results without external lab analysis. Order handheld charger (sold separately) to zero dosimeters and reset scale for repeated use.