This is a very poor company to buy from... So, I purchased an item that was reviewed by Matt Granit...I bought it for my daughters birthday present and so she could use it for her classes. Scientific said it was shipped, we did not receive it...and they couldn't prove delivery. Rather than take care of the issue Scientific screwed around, I had to put the purchase in dispurpte and find another simular item. They don't make it easy to buy from, they don't make it easy to work with...in short they don't care about the Customer.

Shipping is terrible Shipping is terrible! they use Fed X that is usually always horrible with timely deliveries.

Could not find how to open the battery case. The illustration on how to open the battery case did not look anything like what I could find. Nothing.

The axle jumped over the glass holder … The axle jumped over the glass holder because it was to loose for the axle to spin. I had to use a small piece of wood as a wedge to hold the glass to the appropriate distance . Also the axle balance is very poor, I don´t think it´s balanced at all. I wouldn´t recommend it.

Received damaged box with item missing. Ordered on 1/30/17. Received on 2/4/17. Box was damaged and item #3153162 was missing but other 2 items were still in box. I called right away, sent pictures of the box and was told another would be sent right away. Never received it.