The National Optical & Scientific Instruments 447TBL-10 Stereo Microscope is a budget-friendly option with a number of useful features. Setting itself apart from the other microscopes in the 446 series, the 447TBL-10 has 2x and 4x objectives, for 20x and 40x magnification. Other defining features include paired widefield 10x eyepieces, a 360° rotatable viewing head, tungsten illumination, and rack and pinion focusing. There's also a limited lifetime warranty, ensuring the 447's place in your institution for generations to come.
The aforementioned paired widefield 10x eyepieces sit at a 45° angle. A left-side diopter adjustment, an interpupillary adjustment, and reticle holder/retainers enhance their usefulness as well. The tungsten illumination helps to bring specimens into focus with total clarity. Two lights - a top incidental light and a bottom transmitted light - can be operated with the 4-position control. You have the option of turning on only the top light, the bottom light, or both lights. You can also turn both off using the switch.
Sporting an all-metal frame, the 447TBL-10 is tough, able to stand up to daily abuse. The rack and pinion focusing is precise and responsive. However, the microscope also features safety mechanisms, such as a slip clutch and a tension adjustment, that prevent damage. Two 80mm stage plates provide a choice of frosted glass and reversible black/white plastic contrast plates for specimen placement, while locked-on stage clips keep slides secure.