(Carbon) water filters (Cleedownton SY8)

The first is unused (though I've had it for ages). It is notionally for use on a bicycle but could be handheld. In theory you can fill it with stream water and then the carbon filter will get rid of any impurities or bugs. It should be possible to read all the info on the small print
The second filter was used on a trip to Vietnam some years ago when we didn't trust the tap water (in rather remote locations). Similar idea to first filter - you fill it with 'dubious' water which is then forced through a carbon filter. Quantity processed each time is quite small.