My Bumplopedia post seems to have been ignored, so, I will post some pice in this thread.
This is the older version of the Spec. Note the flat thumb stud, straight line texturing in the g10 and 154CM steel.
Newest style. Note the stepped thumb stud, starburst G10 and S30v steel.
Speed Spec, Older straight line textured G10, stepped thumb stud, bead blasted 13C26 blade, a few of these were marked S30V in error (if it has a silver blade with Kershaw markings in tact it IS 13C26).
AL Speed Bump. Stepped thumb stud, Black anodized aluminum scales, 13C26 bead blast blade.
Finally the straight up Speed Bump. Stepped thumb stud, akulon with stantoprene over-mold scales, 13C26 BB blade. (note this knife has been pimped)