From DDL Wiki

Primary Stakeholders and Product Needs

Consumers:
Target Consumers: Backpackers, people without access to clean water (3rd world countries)

• Pumps water
• Drinkability – Purifies well
• Portable (light)
• Pump water quickly
• Cheap
• Durable
• Product lifetime/filter lifetime
• Sustainable
• Easy to sterilize/clean
• Safe
• Non-toxic
• Works with existing products (Nalgene, CamelBaks)

Retailers:
Target Retailers: Outdoor equipment stores/sport stores (REI, Dicks), Internet

• Cheap
• Sustainable
• Attractive
• Profitable
• Safe

Manufacturers:

• Cheap
• Simple design (few parts)
• Compatible with large scale manufacturing processes (Injection molding)
• Easy to assemble
• Standardized/interchangeable parts
• Safe

Shipping/Transport:

• Sturdy
• Light weight
• Compact
• Stackable

Product Function and Evaluation

Usage
Find the cleanest possible source of water. The intake hose is unwound, and then the intake hose is inserted into the water source. Attach the pump to the water container. Pump water at a steady rate, until container is full. Pull the intake hose out of the water, and pump to clear pump of any additional water.

Mechanical Function
The product contains a lever that is attached to a pump with two check valves. On the intake stroke, the intake check valve allows water through the water source into the piston. On the compression stroke, the intake check valve is closed and the bottom check valve allows water to be forced through the filter chamber. The filtered water is then sent out of the pump.