620 589 01 09 00 Socket Wrench Bit - WS28.00-P-0050B

Model 461 with transfer case 750.654/655 

Model 463 with transfer case 750.65 

FG 28/33/Set B 

Socket wrench socket 27 mm octagon, 1/2" square for switch of interaxle differential lock.

Courtesy of MERCEDES-BENZ USA