Picture is of a Mk1, not MkV.
MkV did not have the stearing tail.
Mk1 was used in small numbers at The Somme in 1916.
MkIV was the primary tank used at Ypres and Cambrai in 1917.
The MkIV was also involved in the first tank v tank action against A7V
Only 21 of the A7V saw action as compared to hundreds of tanks deployed by the Allied forces.
The Germans also used small numbers of captured MkIV tanks after Nov 1917, called BeutePanzerIV.
MkV was a later improved version of the MkIV
The model of the MkV should perhaps include the unditching beam, which is fixed to the rails running over the roof.
This was a standard fitting.
Some also carried large facines for crossing wide trenches.