This inventions relates to a stroker device (1) for use in a borehole (2) in the ground. The stroker (1) comprises at least an actuator (6) arranged for displacing a tool (10) in a longitudinal direction of the borehole (2) and grippers (26) arranged to anchor the stroker (1) to the wall (36) of the borehole (2), alternatively to a pipe wall. The stroker (1) is provided with driving wheels (34) or driving belts for propulsion.