The H1-46LPD has been designed specifically for those who have low incoming water pressure. Wether it be a gravity fed situation, long distances from the pressure source, low pressure pumps or for whatever reason these systems are great for this situation. Where filtration is required and only low pressure is available, this can be a frustrating situation as most systems need at least 40psi to push the water through the filters. With the use of the 5uM gradient polypropylene spun sediment filter as the primary filter in the system, you are able to capture a greater amount of sediment within the cartridge without the loss off pressure due to the design of the fiter cartridge itself. This unique manufacturing process gives Purefer filters a true gradient density that allows for a greater dirt holding capacity and higher filtration efficiency compared to standard melt blown filters made from multiple nozzle blowers, giving longer lasting better filtration and less initial resistance or pressure loss. Following this is the secondary 20uM low pressure drop carbon block filter made from 100% coconut husk. As the title suggest these are specifically designed to be used on low pressure giving minimal pressure drops compared to standard filters. LPD Filters are utilised in cases that require the chemical reduction capacity of a carbon block, combined with the flow rate capacity and differential pressure drop of an impregnated Pleated Filter.The coarser micron rating of 20uM allows the filter cartridge to process a higher volume of water with as little resistance as possible.The success of this cartridge comes by way of the special combination of materials and high iodine number to provide chemical absorption you would expect from a standard CTO cartridge, while at the same time having almost 30% less media creating a thinner block wall, allowing water to flow at a higher rate with little resistance. Given there excellent absorbtion qualities these are exceptional chemical reduction filters. All PURE Carbon Blocks are registered as meeting the requirements of NSF/ANSI for Chlorine Taste and Odor, VOCs and THMs reduction.This system is the ideal choice for those on low incoming water pressure. These systems can be used on mains municiple water supplies, tank water, clean dam and creek water, and even good quality bore water. We would recomend the use of sanitation and/ or UV treatment on any untreated water supplies. These systems will not block bacteria and viruses nor will they block cycts such as gardia. Filtration will be abtained to the lowest micron rating of the cartridges which is the sediment filter cartridge at 5 micron.