HVLP stands for High Volume Low Pressure. HVLP and differs from airless spray as it uses air to disperse the material instead of a motor and piston, and uses a turbine to produce a constant flow of air rather than a compressor to fill a tank of reserved air.
The constant flow of air allows for a more even/constant atomisation of the product and because the pressures involved are so low (around 10 PSI) the amount of overspray/mist is dramatically reduced with transfer rates of between 90-95 % achievable.
Turbines are rated in stages, from 1 to a maximum of 5, the minimum Brewers and Spraystore would recommend for decorators to achieve a professional finish is a 3 stage turbine. The higher the stage the higher the air flow rate, aiding the atomisation of the paint, less product preparation with the ability to apply thicker materials and makes the unit run quieter.
The gun has the ability to be adjusted to alter the fan width and the amount of product being delivered so you can go from around an 8 inch fan for larger areas down to a strip about the width of a 5 pence piece for edges and details.