PartyKindom Dial Assorted Resistors Variable Resisters Experiment Tool Safe Plastic

["Experiment tool--it is made of plastic material, and safe, excellent and simple, serving for long time,Physical Tool","Physical tool--plastic material, flexibility and excellent durability, easy to use, for ,Experiment Tool","Very easy and convenient to use, it is very useful and experiment variable resistance box.","It is lightweight, easy and convenient to carry and store when not in use without any effort.","The variable resistance box teaching instrument is suitable and wonderful for school, laboratory use."]