The 2.8 D. Very nice camera. It doesn't have the aura of the F series, but some people prefer the 'classic' Rolleiflex before they started adding fancy geegaws like metering and such. From the height of Rollei's skilled manufacturing days.

DBP and DBGM are German marks, like the US trademark sign (e.g, 'Deutsches Bundes-Patent', previously DRP, 'Deutsches Reichs-Patent', no longer applicable for obvious reasons)