SteriPEN Voorfilter voor flessen met brede hals, pre-filter voor waterflessen met brede hals, 1 maat

ancora non testato sul campo, il filtro è comunque arrivato nei tempi previsti... Si innesta alla perfezione sulla"classica" Nalgene wide-mouth da litro e anche su una Me-ru (analoga). Una volta montato è comunque possibile chiudere normalmente la borraccia col tappo, anche grazie alla possibilità di montare "capovolto" l'elemento filtrante proprio per consentire la chiusura. Se avete acquistato una Steripen (io ho l'Emergency) è un acquisto praticamente indispensabile secondo me.

Easy to use and works well

Over the last several years, I've been using a small, ceramic pump, but it finally clogged up and I decided to throw it out. However, I still had my SteriPen Traveler that I bought in 2016 when I traveled to Kenya. I never used the pen, even on my trips to the Boundary Waters. Instead of buying the MSR Guardian, which I thought would solve all my problems, I went with the much less expensive option of using my never-used SteriPen after finding this Pre-Filter that perfectly seals around my Nalgene. I used it this past summer in the Boundary Waters and it kept nearly all the sediment out, and it allowed me to still use my wide-mouth bottle while making it extremely easy and efficient to sterilize the water.After a while the filter can start clogging with sand and other debris, but i've been able to back wash it to get most of it out. Don't get me wrong, I love my gravity filters, but if you need 1.5 liters of water in 2 minutes, this is the product to buy!

No me gustó pues me resultó incómodo.

I just received this prefilter about one hour ago. Obviously, I have not taken it afield yet to tackle heavily soiled water. Nevertheless, I already tried it on one of my wide mouth 1-liter water bottles, along with my Steripen Ultra. The verdict is that it fits the Steripen and the bottle just as expected. Water leakage to the outside is insignificant without the supplied gasket, and nil with it installed. This said, however -- just to be absolutely sure -- I would not carry my filled bottle inside my pack with the prefilter installed. I would do the prefiltering and the Steripen job, and then carefully store the filter independently from the bottle. This strategy would work very well.The only word of caution that I would have relates to the moderate fragility of the replaceable filter cartridge: carry it protected in your pack because, otherwise, any sharp object could likely puncture the filter fabric. It is for that very reason that Steripen recommends to insert the filter cartridge upside down in the prefilter body when you are storing it after use.The filter cartridge is washable and should provide average hikers good service for a very very long time. If confronted with really dirty water with a lot of sediments, as I have encounterd in some tributaries of the Amazon River, you may want to use the prefilter AFTER having collected that water in another vessel to let it settle for awhile. Then you would be in really good shape preventing near immediate clogging of the prefilter.Have a drink on me!😉