Endorsed for 3rd Class Mail Dispatch 1st Class

1901 FEBRUARY 18: MANILA to MARSEILLE, FRANCE
1901 legal size cover to MARSEILLE (bkstp), apparently regis. (pencilled number), f.w. U.S. Administration 15c pair, 3c (x4, two pairs) & 1c all tied by killers, alongside ms."43" rate and MIL. P. STA. No. 1 MANILA P.I. cds (year inverted), on reverse Manila company h.s., red wax seals, and NAPOLI d.s., corners clipped (indicating printed matter).

3c franking matching the indicated rate at top right corner for proper 35c multiple outbound rate and 8c registration fee. 

The endorsement of "PLANO DE VAPOR MERCANTILE" confirms this to be a printed matter posting (apart from the clipped corners). However I believe this was not accepted as Third Class mail matter but instead as First Class based on a provision that it should be more than 20 identical copies in order for it to pass for Third Class rate.

The  1900-1902 Schedule of Postal Rates that stipulate the Third Class rate as follows: Books, circulars, pamphlets, and, other matter wholly in print, proof sheets and manuscript copy accompanying same. Facsimile copies of hand or typewriting obtained by a mechanical process and easy of recognition as imitations, when mailed in twenty or more identical copies at a post office window; when mailed otherwise or in less number, such matter becomes subject to first class postage............Thus, this letter went out at a rate of 7 times, 3.5 ounces maximum weight (at 5c per half ounce or fraction thereof).