Photoelectric science demonstration kit (electroscope) + list of experiments

Description

Photoelectric demonstration apparatus:
This is a lightly used Klinger Educational Products (Germany) kit, plus a shop-made plexiglass frame to hold a Pen-Ray or similar lamp (we do have one listed separately) and the electroscope. This electroscope charge detection device is a needle that is easily seen to deflect when a charge is generated on the plate. The needle remains deflected until the charge is removed (e.g. by contact with a grounded metallic conductor). In addition to the electroscope, this kit includes a round flat zinc plate, which will emit electrons under the action of UV light, charge the plate, and cause the needle to move, a plastic rod which when rubbed with wool or fur (both included) will be covered with a net negative charge, and a glass rod (Pyrex) which can be rubbed with a variety of materials (e.g., tissue paper, paper towel) to produce a net positive surface charge, and a sheet of emery paper to polish the zinc surface. Also included is a description of 10 simple experiments to demonstrate the photoelectric effect and the fact that like charges repel and opposite charges attract (Coulombs law), the fundamental relationship that governs chemistry.  You get the whole set as shown.
Please look at the photos and ask any questions, thanks.
I do take returns if an item is not as described, of course.  I ship promptly on payment.  I do use tracking, and insure my parcels against loss or damage.  I combine shipping as much as possible so ask in advance if you want to bid on multiple items but let me know, please. If you're in Washington State shipping will be less; and you are welcome to come in person and not pay any shipping cost. Thanks for looking.