Bobcat 863 Timing Cover

[koko]

863, Deutz timing cover has one torx screw recessed in the lower cover. Can anyone tell me what size wrench fits? Also the head has that nub sticking out of the center.
TIA

 

[foton]

I do not know what size it is but if it has the nub it is a security bolt and harbor freight sells a assortment kit of them if it is not to large that kit should cover it.