Locking Hook needed for securing the visco fan coupling during R&R of 8mm hex fastener w/o removing the radiator.
If you must remove the engine fan on your 103, you will most likely need to have this tool. Special tool designed to go behind and insert into a hole on back side of the pulley. This will prevent pulley from turning while removing fan bolt.
ref: same as 103 589 00 40 00 & 903-589 00-40-00
Applicable: Mercedes engines 103 and 104
(Item packaging maybe varied)