Sorry, the Sig550 in Swiss Service is the STG-90 (Assault Rifle 90), the civillian version is the PE-90 (Personal or Civillian Rifle 90) - same gun, in Switzerland the joy is button normally rather temporarily removed, to allow for reconversion if necessary - easily spotted by the metal 'flag' cover on the receiver. Current factory semi auto guns are also PE90, but they are semi-auto 550's. What we get in Canada is NOT a 550, or any subsequent version. That's where the 540 comes in, our guns are closer (but not identical to) the 540 - they are not sold anywhere else in the world, the PE 90 is. Kind of explains the price tag, huh?