Features: 1.Electrostatic Experiment: This foil electroscope is suitable for electrostatic experiment, to check whether the object is charged and whether the charge of the object is positive or negative. 2.Hands on Learning: This physics electrometer is perfect for a hands on classroom experience, mainly used for electrostatic experiments in middle school physics teaching. 3.Designed with Protractor: This foil electroscope demonstrator is designed with protractor, which be used as a pointer electroscope, convenient for teaching and demonstration. 4.High Sensitivity: These foil electroscope teaching tools feature high sensitivity, easily test the insulation of objects and demonstrate induction charging, etc. 5.Compact Structure: This foil electrometer has light weight and compact structure, stable performance, easy to operate and carry. specification:Item Type: Foil Electroscope Material: Acrylic, Metal Use: To Check Whether The Object Is Charged and Whether The Charge of The Object Is Positive or Negative. Inspecting The Insulation of Objects and Demonstrating Induction Charging, Etc. Application Scenario: Classroom, Laboratory, Physics Experiment Teaching Product Size: Approx. 11.4 x 10.5 x 7.4cm / 4.5 x 4.1 x 2.9in ( Manual Measurement, Slight Error May Exist ) PackageList:2 x Foil Plate 2 x Container 2 x Lid