If you have Burton Channel M6 Board and have lost the inserts for the channel then these are the spares you need. These inserts normally come with the snowboard when new but can get lost or wear over time.
These M6 inserts are for the 2011 onwards M6 channel system not the earlier M5 system. Sold as a pack of 4 inserts.
If you have Re:Flex bindings with discs you may also need the hardware for the system Re:Flex pack of spare hardware. If you have other brand of bindings then use the bolts suggested by them for your bindings so not to damage the system.