Browns Bushcraft "The Brown Filter Bag"

The Brown bag is a canvas water filter. It is easy to use and carry. It can be used on its own as a highly effective sediment water filter. It is also effective when used in conjunction with a combined filter/purification system as a pre filter to prevent clogging and extending the filtering life of the system.

Endorsed by SAS survival legend John “Lofty” Wiseman it is available in two sizes; the personal size which holds up to 3 litres and the group size which holds up to 20 litres.

The origin of The Brown Filter Bag

"The Brown Filter Bag" is a product developed back in 2011. It was becoming increasingly more difficult to source the original army surplus mill bank bags. So after nearly three years of trials and testing many different types of canvas Browns Bushcraft traced the original manufacturer of the military canvas used in the millbank bags. The canvas was woven as a special order to the exact same specification as the original military bags. The new canvas was woven to an approved MOD specification but without the potential harmful copper anti rotting compound found in the early military bags. Both the canvas and the manufacturing of the bags is now carried out within the UK.

What is The Brown bag designed to do?

Making water safe is a two stage process. 1st Filtration 2nd purification. The Brown Filter Bag can be used for the first stage of making water safe, filtration. It is designed to filter turbid or dirty water. Turbid water is water with suspended sediment in it such as sand, mud, silt or organic matter. It is essential to remove the sediment as it provides hiding places for water borne pathogens e.g. Viruses, bacteria and parasites. If the sediment is not removed this is known to reduce the effectiveness of chemical purification treatments on these pathogens. In addition, if the sediment is not removed it can upset your digestive system.

What are the advantages of The Brown Bag?

It is compact, lightweight, very durable, virtually unbreakable and it has an unlimited filtering capacity. Due to its compact size and lightness it can be easily stored and carried in your everyday essential kit.

Using your Brown bag for the first time.

Prior to using your brand new Brown bag on your next trip, expedition or adventure it is essential that the new bag is broken in before. The fibres and weave of the canvas need to be loosened up and opened in order to maximise its performance.

How to break in your new Brown bag.

1. Saturate the bags in water, squeeze the water through the bags to unsure they are fully wetted. 2


2. Then be rough with them! Scrunch them up, massage and squeeze the bags. This will help to soften the canvas and open up the fibres.


3. Repeat the process 3/4 times allowing the bag to dry in-between.


4. You can also put the bags in the washing machine. Place in a clean washing machine on a cold rinse cycle with NO detergent and NO fabric softener. Always remove the paracord before placing in washing machine.

How to use the Brown bag

Once you have found a source of water to be filtered make sure you have a suitable point to hang the bag from when its full of water. You can for example use a tree, tripod or vehicle.

1. Start by thoroughly soaking the bag in water, massage the water through the bag to ensure it is saturated.


2. Fill the bag to the top with water to be filtered. It sometimes helps to use a cup to scoop water in to fill the bag to the top.


3. Allow the water in the bag to flow down to the stitched line that’s runs across the front of the bag approx. ¼ of the way down the bag. Do not collect this water, allow it to run onto the ground. This helps remove any debris on the outside of the bag and prevent it from dropping into your collecting pot.


4. Once the water has flowed down to the line you can place a vessel under the bag to collect the filtered water. If the water is very dirty you can always pass it through the bag a second time. The water will take between 5 and 10 minutes to pass through the bag.


5. Once the water has been filtered it must be purified. Although it may look clean it may contain pathogens which need to be removed by purification. The water can be purified by being brought to a rolling boil, adding chemicals or using a purification system.

After use and care

After each use turn the bag inside out and remove any built up sediment and debris. You can wash it out in clean water or allow the bag to dry out, this enables you to knock the dried sediment out once dried. Make sure the bag is thoroughly dried before storing away for your next adventure!