Armour Safety have 4 types of disposable mask for respiratory protection.
The SC600 is a basic dust mask with a single elastic strap stapled to the mask. It is rated P1 meaning it provides protection from particles, dusts and mists such as those produced by sawing, sanding, stripping, planing, drilling, grinding and routing timber. It also protects against wet sprays and dusts created when working with concrete, bricks, fibreglass and other masonry products.
The other 3 disposable respirator masks (SC601, SC611 & SC602) are all rated P2 meaning that they do everything the P1 mask does plus they also protect against thermally generated smoke and fumes generated by welding, soldering, bazing and metal cutting. All of these masks conform to the safety standard AS/NZS 1716:2003. They all have double elastic bands that are sealed onto the mask so they won't break as easily as many of these masks where the bands are stapled to the mask. They have an adjustable nosepiece and inner foam to provide a custom seal for different face sizes and shapes. These masks are made of loaded polypropylene to provide low breathing resistance yet high filtration efficiency.
The difference between the 3 masks is that the the SC611 and SC602 have a silicon exhalation valve that resists dust while making it easier to breathe while the SC601 does not. The valve opens to allow the outward breath closing immediately the user breathes in. The outward breath therefore can dissipate more easily and doesn't fog up safety glasses.
The difference between the SC611 and SC602 is that the SC602 has an additional active carbon layer (which is why it has a charcoal colour). This resists toxic gases, fumes, acid vapours and micro dust.