Also available as a kit which includes four of these glow plugs and the glow plug control unit, see below
Sprinter II 2014-2016 OM651 4 Cylinder Diesel
Do not try to remove glow plugs from a cold engine.
Before attempting to remove any glow plugs, start the engine and allow it to reach operating temperature. Failure to do so will most likely result in shearing a glow plug off in the aluminum cylinder head. Before installing any new glow plug, coat the new glow plug threads with a good quality anti-seize compound, in order to facilitate easier removal in the future.