Description: 【Product Type】: This is a Physical Resistance Experiment Set, for hands-on learning about physics and resistance. Learn basic physics principles and conduct experiments with the resistor substitution box to study physics 【Material】: The physics resistance lab experiment is made of sturdy pp material, ensuring it can withstand repeated use in a classroom or home setting. 【Product Dimensions】: The compact size of the kit (9x9x2.5cm) makes it easy to store and transport, making it ideal for both school and home use 【Package Contents】: Each package contains 1 set of the 0-999 ohm Resistance Substitution Decade Box for students to further understand the basic principles, learn the basic electromagnetic experiments 【Educational Tool】: This Variable Resistance Box serves as an Physical educational tool for middle school students to learn about physics in an interactive and engaging way, which not only can improve their physics learning skill, but also can improve their hand-on ability Specification: Material: PP   Size Chart: 9cmx9cmx2.5cm/3.54inchx3.54inchx0.98inch   Package Includes: 1x Physical Adjustable Resistance Box   Note: 1.This is not infant toy , please take away from children to avoid eating. 2.Please allow slightly errors 1-2cm differences due to manual measurement.