eggbox (cadbury box or similar)
you need a heatmat that will sit in the base or lid of the polybox. It doesn't need to be powerful, but it does need to be above the minimum wattage for the stat. A pulse stat is probably best but a matstat (on/off) will do.
put the matstat on the bottom or lid and plug into the thermostat. Plug the thermostat in and put the probe near the eggbox. Leave to stabilise for a day or so.
Fill eggbox with damp vermiculite add eggs and watch for ages.
Make sure the eggbox has some airholes. Ideally you should see some condensation, but it shouldn't drip. Be careful when opening that you don't get water on the eggs. If you need to add water, drip it sparingly in a corner away from the eggs. I never found much use for a hygrometer
good luck with the tortoise eggs. I never heard of people breeding tortoises before.
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