Remove the foreign object 
Use pliers to extract the object from the tire. Then, mark the damaged spot with chalk. 

Ream the injury 
Use a carbide cutter (reamer) to drill through the puncture channel several times — from both the outside and the inside of the tire. 

Prepare the STEM plug 
Remove the protective foil from the STEM plug and apply Super Valkarn G vulcanizing cement onto it. 

Lubricate the injury channel 
Insert a small amount of Super Valkarn G cement directly into the puncture channel. 

Insert the plug 

Trim the inner side of the plug 
Cut off the excess plug material on the inside of the tire, leaving about 2–3 mm protruding above the surface. 

Prepare the patch area 
Place the universal patch over the plug on the inside of the tire and outline an area slightly larger than the patch using chalk. 

Chemical cleaning and roughening 
Use Liquid Buffer to clean and chemically roughen the marked area. 
Scrape off remaining dirt and grease with a scraper. 

Mechanical roughening 
Use a low-speed grinder to mechanically roughen the prepared area thoroughly. 

Clean the surface 
Use a pneumatic vacuum to remove all dust and rubber debris from the repair surface. 

Apply vulcanizing cement 
Apply Super Valkarn G cement evenly across the prepared area. 
Wait until it is completely dry before continuing. 

Apply the patch 
Remove the aluminum foil from the back of the patch. 
Carefully place the patch onto the tire, making sure not to touch the bonding surface with your fingers. 

Press the patch 
Firmly roll the patch from the center outward using a stitching roller to eliminate air bubbles and ensure full adhesion. 

Trim the external side of the plug 
Cut the protruding end of the plug on the outside of the tire, leaving about 2–3 mm above the surface. 

Seal the repair 
Apply Maruni SEALINER over the repair area to prevent air leakage. 
The repair is now complete.