O FIRST SOS It is suitable for difficult nails and prepares the natural nail by reinforcing the adhesion of gel, gel, acrygel and acrylic varnishes to the natural nail. Avoid contact with cuticles and skin. Contains acid.
Explanatory video here
Apply Primer SOS to the entire natural nail, without touching the cuticles. Air dry in 30 to 60 seconds. Apply small amount.
NOTE: You can use only the SOS Primer or only the Bond Promoter or you can use both as follows: first Primer SOS and then Bond Promoter