Pull/Expand principle. The installation tool maintains sleeve position in the hole while pulling the mandrel into, and expanding the sleeve until the mandrel breaks off at a predetermined point. Anchorage is achieved by the serrations on the outside of the sleeve anchoring into the base material, especially in soft material.
The installation is also based on the Pull/Expand principle. Thanks to the soft sleeve material, anchorage is achieved by the flow of sleeve material into the surface roughness of the drilled hole. The HK series plug is especially suitable for the use in hard materials.