Bolt head spare parts kit made of high quality materials.
 
Parts in this kit:
gas rings (3 pcs)
ejector
ejector spring
ejector pin
extractor
extractor spring
extractor pin
 
It is recommended to change all the listed parts AT LEAST every 10 000 rounds to prevent cycling and case extraction malfunctions. Still, it is always a good idea to have this spare parts kit ready in your range bag.