Hardness
Point, shank and head are heat treated and tempered in a controlled atmosphere to a hardness of Rockwell C-50

Corrosion
Resistance
Gripnail fasteners are plated with .0002" to .0003" of zinc and receive a final chromate dip. This plating exceeds current SMACNA standards for corrosion resistance.

Retaining Cap
Retaining cap is sufficient in size and design to depress the surface of the insulation without tearing or cutting it. The cap does not protrude into the air stream to create noise or interfere with air movement in the duct.

Temperature Range
Gripnails function properly over normally accepted operating range of temperatures of 32 degrees F to 250 degrees F and are not adversely affected at temperatures of 0 degrees F to 550 degrees F.

Vibrations
Gripnail fasteners will not fatigue or be physically affected by vibrations normally found in high velocity air handling systems.

Environmentally Safe
When used as intended, Gripnail Fasteners are non-toxic and safe as defined by current Federal Standards. Safety glasses must be worn when applying fasteners at all times.