as of serial number 05.5000/01370 and 05.6000/00589
P-5 cl - 05.5000/0492 and 05.6000/0380
as of serial number 05.50xx/322 und 05.60xx/322
as of serial number 05.500/298 and 05.600/298 - speed range between 30 and 400 rpm
as of serial number 05.500/101 and 05.600/101 - speed setting between 30 and 400 rpm
as of serial number 05.302/101 and 05.402/101 as of 02/1998 - English version on request
as of 06/1990 to 01/1993, serial number 05.102.00 and 05.202.00
as of 1987 - The instrument is equipped with a Perma-Drive motor and control from serial number 1954 to 2985, except for serial numbers 1960, 1961, 1970, 1976
as of serial number 50.212.00 and 50.217.00