On auction , this brass lens made by : C.E. Riese Berlin.Serial No: 8149. The lens is in good condition , glass looks reasonable clear , with signs of old age , more then 100 years old . Hight : 6cm. Diam front : 5,4 cm. Thread size : 5,47 cm Diafragma from 6.8 --44. Please see all pictures as they are part of the description. Note that : Import duties, taxes and charges, are not included in the item price or shipping charges. These charges are the buyer's responsibility.