The Mamyia Sekor E was one of the last lenses added to the Sekro E lineup, together with the Sekro E 3.5/35-105mm. Like the 35-105mm, I have never seen it pictured in brochures or leaflets, and very little information can be found online. The lens probably was desigend as a cheaper successor to the earlier Sekor E 3.8/80-200mm, but porduced only in small quantities. My sample has SN 10084, indicating th 84th lens produced. Unlike its precedessor, the "new" 4/80-200mm lens is a one-touch-zoom with a reduced MFD of only 1.0 m (instead of 1.2 m). 

As with all Mamyia Sekor E zooms, the barrel is completely made of metal (apart from the aperture ring), but it feels a bit less solid than the previous 3.8/80-200mm lens, mainly because of zoom creep. Focusing is not as smooth as with the earlier telezoom, and slightly wobbly. I haven't seen a lens section anywhere (not sure if it was published by Mamiya at all), but I assume it is a common [13/9] or [12/9] four group zoom layout.

The perfomance of the "new" E 4/80-200mm is not as good as the E 3.8/80-200, especially above 135mm. At longer focal lengths the lateral CAs are much stronger, and corner resolution at f=200mm isn't as good as with the earlier model. The E 4/80-200mm therefore is more a collectors item, a rare oddity at the very end of Mamiyas lens production for 35 mmm SLRs. 

The lens sectipon below was taken from the Rolleinar MC 4/80-200mm, which was produced by Mamiya and sold by Rollei between 1984 and 1989. The pictured air spaces between some of the lenses probably aren't real, but we certainly get an generic idea of the construction of this rare Mamiya E lens.

MAMIYA SEKOR E 80-200mm 1:4                  (13 lenses /  elements)