Kessel Staufix FKA Instructions De Pose Et D'utilisation page 30

Fitting the cover plate
Fit the seal on the underside of the cover plate.
Grease the seal on the outside.
Fit the cover plate into the upper section click-in lug first.
Use the key to lock Lock & Lift.
Tileable KESSEL cover plates can be tiled using neutrally
cross-linked silicone or grouting material on an epoxy
resin basis. Grouting must always be cavity-free, using a
sealing material to match the tile material.
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