The SteriPEN is an eco-friendly gadget ideal if you’re travelling to areas with typically unsafe drinking water. The SteriPEN will allow you to refill your water bottles (rather than buy bottles from a shop) and ensure the water is safe before you drink it. The pen uses shortwave ultraviolet light which damages the DNA of bacteria, viruses and protozoa, rendering them harmless.
It takes just 45 seconds to sterilise 500ml of water. A single charge of 4xAA batteries can treat up to between 90 and 105 litres of water. If you use a rechargeable battery (such as with a solar charger), the SteriPEN is completely portable and green.
The SteriPEN costs around $90, or about £50-£70 in the UK.
Source: Urban Green Girl