Tagging Question ... Electric Auto

I've read about the various tagging styles (Large block, small, overall, mottled, etc.) And I've even seen some sets where the tagging is obviously offset to a great degree. In this example, I have a Length of (5) - though only the last (4) are shown. Not the best example of a US 1906, but I thought the tagging in the last stamp looked odd. Is this some sort of "transition" tagging pattern?

(Note the paper is slightly warped, but, unfortunately, the right bottom is torn ...)

Partime, that is a bottom tagging clip. The tagging was applied by the Cottrell presses on this issue. The printers at the BEP used precancel mats to apply the tagging. For this operation they shaved the precancel mats down, so the bars and wording were no longer visible. The mats were connected to the printers rollers by means of clips and / or screws.
Where a clip or screw was placed a small portion of the mat was removed so as to keep the surface smooth. At that location no tagging was applied. The vertical "bar" above the clip is the tagging mat's "joint line"; where two tagging mats meet! Hope this helps?

Peter

Very neat! One more comment to put in my collection. Thanks again to SCF.