German anti-aircraft gun sight:  Rundblickfernrohr Fur Flak, maker code bvu with blue triangle for central Europe weather condition use.  Matching tan painted steel case marked:  Rbl.  F. Flak.  Lid of case has rubber eye cup in holder and instruction plate.  Case code:  hhu, 1944 date, and acceptance WaA83.  All items excellent plus. $275