Purify your water without using any chemicals – with the Adventurer Opti UV from Steripen. Conventional water purifiers typically use chemicals to clean out bacteria and germs from water, but the Adventurer Opti actually uses UV radiation for purification instead. Here’s how to use the device: place the long stick into your water bottle and then start stirring evenly and it’ll be activated for 48-90 seconds (depending on the volume). And just like that, you can immediately take a sip of your purified water. In addition, since no coarse particles or chemical substances can be filtered out, it’s best to use it on relatively clear water located far from a town or factory. But, you probably won’t be trekking in the city anyways, right? Plus, the Adventure Opti uses two CR123 batteries, which are included in the delivery, and it can be used in 0.5 to 1 litre containers for up to 8000 times. The opening of your bottle should be at least 4.45 cm wide due to the shape of the device. An added bonus: it comes equipped with an integrated LED torch!