Undercut anchors

KEIL Undercut Anchor

KEIL Undercut Anchor KH AA

555 020 ---

Anchor sleeve and hex bolt with locking ratchets, stainless steel A4

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

Product information

  • The undercut anchor consists of an anchor sleeve with matching hex bolt with locking ratchets (screw).
  • Drill hole, anchor sleeve and screw length must be matched to the desired insertion depth and the bracket of choice. Only the use of matching parts will make the assembly quick, simple and safe.
  • Insert the at the base compressed anchor sleeve, together with the required bracket,
    into the undercut hole.
  • Screw in the screw, exerting gentle pressure on the bracket (in order to fix the anchor). The locking ratchets of the screw will cut into the bracket, securing the screw.
  • The anchor sleeve is expanded to its original dimensions by inserting the scew to a controlled depth, making it sit snugly against the panel in the undercut area of the drill hole. After the assembly, the anchor will sit in the undercut hole free of expansion pressure (i.e. the bracket can still be rotated with a certain amount of physical effort).


  • Natural stone
  • Artificial stone
  • Manufactured stone
  • Ceramics
  • High Pressure Laminate (HPL)
  • Synthetic material
  • Fibre cement
  • Glass fibre reinforced concrete (GFRC)
  • Glass ceramics
  • Solid surface materials
  • Ultra high performance concrete (UHPC)

Instructions for use

  • Use according to approval and KEIL assembly instructions for undercut anchors.
  • Please find documents with relevance to building regulations under certificates.

Packaging units


KARL Undercut Anchor

KEIL Fasteners

KEIL reveal attachment sets

Drilling tools

Diamond tipped façade drill bits

Carbide tipped façade drill bits

Drilling technology

Drilling machines

Machine Accessories

Spare parts

Assembly aids

Depth control guide

Assembly aids

to the