Levenhuk 400 Series 40-1000x Microscope

The 400 series is Levenhuk's starting point for laboratory microscopes, in two versions that share a metal body, a lower LED with a collector lens and the option of running on three AA batteries. The 400M has one eyepiece and stops at 400x, and Levenhuk lists it for schools and beginners. The 400B has two eyepieces, a fourth objective for oil immersion and reaches 1000x, and Levenhuk aims it at a microbiologist, a vet or an ecologist.

Both use achromatic objectives of 4x, 10x and 40x, with the 40x on a spring so it gives way if it meets the slide. The 400M pairs them with a single WF10x/18 mm eyepiece with a pointer, on a head set at 45 degrees. The 400B adds a 100x oil objective and a pair of WF10x eyepieces on a 30-degree head, with eye spacing from 48 to 75 mm and 5 dioptres of adjustment each way, and a bottle of oil is in its box. Each head turns a full circle.

The stages differ as well. The 400M has a fixed 110 by 110 mm stage with clips and a condenser of N.A. 0.65 with an iris diaphragm and a filter holder. The 400B has a mechanical double-layer stage of 115 by 110 mm, which knobs move 55 mm and 20 mm, over an Abbe condenser of N.A. 1.25. Focus on both is coaxial, 12 mm coarse and 0.002 mm fine, and the 1 W LED dims and runs from the adapter in the box or from AA batteries, not included. Our guide to using a microscope covers setting the condenser and the iris.

Blue, green and yellow filters and a dust cover come with both. For a child or a family, the Rainbow 50L PLUS is the friendlier choice, and the 320 PLUS above this one reaches 1600x. The rest of our microscopes for schools sit alongside it.