450 589 09 99 04 Box wrench bit - WS42.00-P-0070-04B

FG29/42/Set B 

MODEL 450, 451, 452 

Use: 

Open ring wrench socket for loosening and tightening the union nut on the brake lines.

Fig 1: Identifying Box Wrench Bit (450 589 09 99 04)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.