Kontax are one of the better quality makes of low temperature Stirling engines.
This is a fairly conventional low temperature Stirling engine, except that it's made to a high quality standard. It's claimed to be able to run off the heat from a hand, although I've found this is only so if the air temperature is low enough. It will run on my naked thigh at room temperature! It will also run on a block of ice and, of course, a mug of tea. It has miniature ball bearings in the crank shaft and a graphite power piston in a glass cylinder. The power cylinder is 9.5mm bore x 8mm stroke. The displacement piston is 70mm diameter x 7mm stroke. Condition is used but almost as good as new. This example comes with the optional glass dome cover.| Make | Kontax |
| Model | KS90 |
| Made | 2010s? |
| Description | Low temperature Stirling engine |
| Cylinders | 1 |
| Cylinder Type | Single acting, graphite in glass |
| Bore mm | 9.5 |
| Stroke mm | 8 |
| Mechanical Condition | Good |
| Cosmetic Condition | Good |
| Paintwork | N/A |
| Purchased | 3/4/2018 |
| Purchase cost | £40 |
| Additional cost |