A collection of portable personal dosimeters (pencil chambers) together with three battery-based charging units. The dosimeters, which are direct reading, measure 11 cm in length while the battery-based charging units are 9 cm wide. No indication as to the manufacturer nor the voltage and type of batteries used is indicated on the charging units. The battery was inserted on the left-hand end while the dosimeter port was on the right-hand side. A thumb-wheel is used to set the amount of charge on the anode. The range of the dosimeters varies with some reading a maximum of 0.2 R while others have a maximum of 0.5 R.
