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Description
Laser Double-Slit STEM Box (includes 12 different "Beam-Splitters")This new and improved STEM Box includes everything you need to achieve an interference pattern with a laser in less than 60 seconds, like Thomas Young's classic double slit experiment (we love the following animation of how light is thought to propagate past a double slit, from: File: Double slit experiment. webm Wikipedia) : Your browser does not support the video tag. What's New: No wire or tape needed 12 different widths of "Beam splitter" Hand
This new and improved STEM Box includes everything you need to achieve an interference pattern with a laser in less than 60 seconds, like Thomas Young's classic double-slit experiment (we love the following animation of how light is thought to propagate past a double-slit, from: File:Double slit experiment.webm - Wikipedia) :
What's New:
- No wire or tape needed
- 12 different widths of "Beam-splitter"
- Hand-crafted from Canadian Maple
- Brushed aluminum backing
Included:
(1) Class IIIA, or 3R red laser, serving as a coherent light source. Power of <5mW, and wavelength of ~650nm. Your choice of body colour for the laser (as supplies last).
* Class 3A laser, also known as Class IIIA or 3R laser, is a low-powered laser that emits visible light between 1 and 4.99 milliwatts. It is considered safe when handled carefully, but it may cause eye damage if stared into or viewed with optical devices such as binoculars or microscopes. It is not a skin or material burn hazard. It is the maximum class allowed for laser pointers in the USA and Canada (from Per Chat GPT 4.0, on Mar-24-23).
(2) Double-Slit Assembly, serving as a way to split the coherent laser light beam into a diffraction pattern. Includes 12 very thin wires, from AWG 28 to AWG 50. Handmade in Canada of locally-sourced Canadian Maple. Dimensions are 180mm Length x 31 mm width x 9 mm height. Mass: 41 grams (approx.) (excl. jewel case).
(3) Straight-forward step-by-step illustrated instructions (for an adult) so that you can easily and successfully perform the double-slit experiment at home in less than 60 seconds
(Hint: we find it works best to hold the assembly at least ~1 meter from a wall or other screen, and that anything closer than ~0.5 meters becomes quite difficult to see).
(4) A kid-friendly explanation of the experiment.
Using the materials in this STEM Box, you can see for yourself how different wire widths, distances, orientations, etc. affect the laser interference pattern.
You might also wonder: how does the wavelength of red laser light (about 650nm, or 650 billionths of a meter) compare to the thickness of the 12 different sized wires included in the Assembly (the "beam-splitters")? Table A provides this information, and we've also laser-engraved most of it on each Assembly for easy reference using a Glowforge laser:
We've included in Table A a "Multiple of Wavelength of Red laser light" (far right column) to give users a physical sense of how vanishingly small 650nm really is. We find the tiniest wire (AWG 50) to be barely visible, and yet its 0.025mm thickness is still equal in length to 39 full wavelengths of 650nm red light (!!!).
For a brief demonstration of how the double-slit experiment can be performed at home using a laser, electrical tape, and AWG 32 wire, check out the following video that inspried us early on:
For the truly daring (and make sure you're sitting down for this little dose of reality), check out this video:
And more recently, check out these videos from Floathead Physics, Fermilab, Answers with Joe, and Astrum:
Recommended for Age 12 & Up (with adult supervision)
Shipping Notes
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Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.5 ★★★★★
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Product Reviews
★★★★★ 5
check to make sure if you need the roller brush too.
fits perfectly
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Reviewed in the United States on April 28, 2026
★★★★★ 5
Spark plugs
As advertised
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Reviewed in the United States on April 27, 2026
★★★★★ 5
Fits well, sane quality as the oem installed
Works really well, it fits and matches the original spark plugs and very easy to install. Very affordable! It starts right up , quality is very good and didn't have to adjust the gap on spark plugs!
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Reviewed in the United States on July 5, 2025
★★★★★ 5
Fresh Spark Plug for the Mowing Season
Just what my push mower needed! Very compatible with my Craftsman M220 push mower. It was the right replacement part and workings just like the original brand B&S plug. Gap was correct right out of the box as my push mower fired right up first pull. Would recommend for anybody with a Craftsman M220.
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Reviewed in the United States on April 14, 2026
★★★★★ 5
Good spark
Good fit. Fired right up
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Reviewed in the United States on May 13, 2026
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