• Blue collapsible water bladder set with a matching blue drinking tube, black carabiner clip, white straw, and a portable filter straw, shown against a mountain lake background. big green bear biggreenbearcom
  • Blue 3L gravity-fed water bag set with an adjustable strap, blue filter straw, extension tube, and screw-port adapters, shown over a scenic mountain-and-water background with product labels.
  • A blue collapsible water filter pouch with a tube and filter cartridge, shown over a mountain-and-water outdoor background with promotional text callouts about chemical-free use, 5-year shelf life, low 300ml/min rate, up to 4,000-liter filtering capacity, and BPA-free materials.
  • A blue and white cylindrical water filter device shown on a scenic mountain lake background with promotional text about layered high-efficiency filtration, hollow ultrafiltration fiber membrane, activated carbon fiber, and use cases like hiking, camping, and first aid.
  • A portable water filter straw shown next to two glasses of water labeled pre-filtration and after filtration, set against a scenic mountain lake background with text explaining impurity filtration.
  • A blue 3L/102 oz water bag shown in a camping scene with a lake, mountains, and a tent in the background, alongside marketing text and feature icons including BPA-Free, Food-Grade, Sturdy & Durable, and Easy Cleaning.
  • Blue collapsible water bladder shown in a mountain lake setting with overlaid dimension labels and text reading 'COLLAPSIBLE SMALL SIZE LARGE CAPACITY.' A hand is holding one bladder, and the image includes multiple views and measurement arrows.
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Biggreenbear.com

3L Gravity Water Filter with Tree Strap

3L Gravity Water Filter with Tree Strap

$39.89 USD
$39.89 USD
Sale Sold out
Taxes included. Shipping calculated at checkout.

Big Green Bear

3L Gravity-Fed Water Filtration System | Portable Camping Water Purifier

Never worry about clean drinking water on your outdoor adventures again. The Big Green Bear 3L Gravity-Fed Water Filtration System is your ultimate survival and backcountry companion. Engineered for hikers, campers, and emergency preparedness, this high-capacity system turns natural water sources into pure, crisp drinking water completely hands-free using nothing but the power of gravity.

Why Choose the Big Green Bear Gravity Water Filter?

  • Advanced Double Filtration: Features a two-stage 0.1-micron hollow fiber membrane combined with an activated carbon fiber core to eliminate impurities and improve taste.
  • Massive 3-Liter Capacity: Perfect for base camps, group hiking trips, and family emergency kits.
  • Multi-Use Versatility: Use it as a gravity camp system, drink directly through the straw like a life-straw, or attach it to your favorite water bottles and extension tubes.
  • Ultra-Durable & Safe: Built from food-grade, heavy-duty, BPA-free material designed to withstand rugged outdoor environments.

Product Specifications

Feature Details
Purification Method Activated Carbon + Ultrafiltration (UF) Membrane
Filtration Pore Size 0.1 Microns
Filter Lifespan Hollow Fiber: 6,000L (1,500 Gal) | Carbon: 300L (80 Gal)
Material Food-grade, BPA-Free TPU / Plastic
Capacity 3 Liters (102 oz)
Dimensions 8" L x 3.5" W x 12" H
Power Source 100% Gravity Fed (No pumping or batteries required)

How it Compares

Feature Big Green Bear Gravity System Standard Pump Filters Traditional Squeeze Filters
Operation Hands-Free Gravity Manual Pumping Manual Squeezing
Capacity 3 Liters Single Bottle Single Bottle
Filter Life Up to 6,000 Liters ~1,000 Liters ~2,000 Liters
Taste Enhancement Yes (Carbon Filter) Rarely Included No

How to Use Your Gravity Water Filter

  1. Fill the Bag: Scoop fresh water from a river, lake, or stream directly into the 3L blue gravity bag.
  2. Hang the System: Use the adjustable tree strap to secure the bag to a sturdy branch or post high above the ground.
  3. Connect the Components: Attach the hose to the bottom link of the bag and connect it to your filter straw.
  4. Let Gravity Work: Open the inline valve clamp. Pure, clean water will flow freely into your water bottle, cooking pot, or directly into your mouth.

Care & Maintenance Instructions

  • Backflushing: Periodically flush clean water backward through the filter straw using a syringe to clear out caught sediment and maintain a fast flow rate.
  • Air Dry Before Storage: Disassemble all parts and allow them to dry completely to prevent mold or mildew growth before long-term storage.
  • Replace Filters Regularly: Swap out the inner carbon core every 300 liters to ensure the best possible water taste.

What’s In the Box?

  • 1 x 3L Heavy-Duty Water Bag
  • 1 x Dual-Stage Filter Straw (Hollow Fiber + Carbon Core)
  • 1 x Adjustable Tree Hanging Strap
  • 1 x Detachable Extension Tube with Flow Clamp

Frequently Asked Questions (FAQ)

Can this filter remove salt from ocean water?
No. This system is designed for freshwater sources like lakes, rivers, streams, and rainwater. It cannot desalinate saltwater.
Are the replacement filters available?
Yes! Both the long-lasting hollow fiber filter and the flavor-improving carbon cores are fully replaceable.
Does it filter out viruses?
The 0.1-micron ultrafiltration membrane safely removes 99.999% of bacteria, parasites, microplastics, and sediment. For suspected viral contamination, treat the water chemically after filtration.

The Big Green Bear Promise 🐻

Shop with absolute confidence at Biggreenbear.com. We back our gear with a rock-solid 30-Day Money-Back Guarantee—if it doesn’t live up to your outdoor standards, send it right back for a full refund.
We provide Fast & Secure Shipping within the USA directly to your doorstep so you're fully prepared for your next trek. Don't risk your hydration on the trail; secure your ultimate camp setup today!
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