Late in 2005 Hot Wheels released 500 Master Sets of all 1:64 die cast cars (including all the AcceleRacers die cast vehicles). These factory boxed cars where each marked with a holographic sticker with the words "2005 Master Set" - otherwise they are standard issue die cast cars. If you see a AcceleRacers Master Set, be aware that these cars were separated from the original full Master Set some time in the past.