HDB is a new needle style which is yielding very good results in many applications. Some of these are in needlepunching spunbonds for geotextiles, others are applications where surface smoothness is most important, and also as a finishing needle in a multi-loom needling line.

HDB is a new barb spacing named High Density Barb spacing. HDB barbs are spaced at .052 inches (1.3 mm) apart on each apex of a Triangular or Pinch Blade. As such the barbs are approximately 60 percent closer together than the next standard barb spacing, which is Close Barb spacing with .125 inches (3.2 mm) barb separation.

Additionally, special Foster Formed Barbs were designed for use on the HDB styles which are not found on other needle blades. And these barbs are small - about 1/2 the size found on the same blade gauge using CB and RB spacing.

With these specially designed barbs, at smaller than normal depth, spaced approximately 60 percent closer together, HDB styles offer the following advantages:

1. Increased fabric integrity and higher tensile strengths
2. Reduced fiber/filament damage
3. Smoother fabric surfaces
4. Ability to use much lower penetration depths