Here's a review of the "Mustool" G600 LCD display microscope, including some examples of what we might use it for. Operation is simple and results are quite acceptable - it has an internal adjustable light source and will go up to a 600x magnification. For a modest priced item it fills a useful niche in the shop for inspecting such things as tool grinds and condition etc.
Mustool G600 Digital microscope: https://goo.gl/5fJc3F
15%off coupon code: 8a68ae
Optical Instruments with 15% off: https://goo.gl/wmXETx
( http://www.oldmansshop.com/ )
