Buckle Replacement is necessary when buckles are worn or corroded and when changing the outer moulding of face-masks.
Cold forged, from Brass 121, the buckles are Nickel plated and very easy to fit; simply pushing the tangs in to the sipes in the mask moulding and pulling back, so that the ends of the tangs capture the rubber, as shown.
To remove the buckles from your old mask: release and remove the head harness and bend each buckle over the top of its anchorage. The tanks (retaining it in position) can then be wiggled to release them, by pushing the tangs back under the anchorage moulding. Note the 'How-to' pictures, in the main images panel.
Typically; the task of changing the rubber mask moulding will be more frequent if you are using silicone rubber (usually Black or Yellow) versions of the mask because silicone rubber is inherently less strong and elastic than the special rubber compound, used for the grey (NR) mask.
The compound for the grey mask is a mixture of natural, Neoprene and Strene Butadiene rubber, aimed at reducing skin reactions; for all-day-comfort and lending better strength, elasticity and durability to the mask.