Undercut anchors

KEIL Undercut Anchor

KARL Undercut Anchor

KARL® Undercut Anchor KH AA

520 020 ---

Anchor sleeve and hexagon head bolt with locking ratchets made of stainless steel in quality A4

D1 = drill hole Ø
D2 = undercut Ø
SW = shaft spanner gap
XA = anchor hex

further dimensions on request

  • The KARL® undercut anchor consists of a self-undercutting anchor sleeve and the corresponding hexagon head screw.
  • The anchor sleeve, compressed in the lower area, is inserted into the cylindrical drill hole.
  • Rotating, the anchor creates its undercut itself. This is done by inserting the pin of the setting tool clamped in the cordless drill in a path-controlled manner. The anchor is driven by means of the hexagon socket of the setting tool. The anchor sleeve is expanded to the initial dimension. Thus, it always lies fully against the undercut area of the drill hole of the facade panel.
  • With slight pressure on the plate holder (to lock the anchor), the screw is screwed in. The locking ratchets of the screw dig into the plate holder as a screw lock. After assembly, the anchor is seated in the undercut hole without expansion pressure, i.e. the bracket can still be turned with a certain amount of force.
  • The drill hole, anchor sleeve and screw length must be matched to the desired setting depth and the selected plate holder. Only the use of matching parts makes installation quick, easy and safe.
  • KARL® undercut anchors are externally monitored.


  • Fiber concrete
  • Fiber Cement
  • High-pressure laminate (HPL)
  • Compressed fiberboard

We would be happy to test the usability of our undercut anchor in your material as well.

Packaging unit


Instructions for use

Application according to KARL® installation instructions for anchors

KEIL Fasteners

KEIL reveal attachment sets

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Carbide tipped façade drill bits

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Spare parts

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Depth control guide

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