This 6-point "spinner" driver from Beta Tools features a sliding T-handle that can be removed for compact storage. It also let you turn the T-handle into an L-handle for maximum torque, then back to a T-handle for quick fastener spinning. 6-point nut driver fits any metric nut or bolt with a standard 16mm hex. 260mm overall length, 200mm handle length. Hex is 12.5mm deep with a further 26mm deep recess to accomodate bolt threads.
This size is also available in the Beta Tools 950/S14 14-Piece Sliding T-Handle Metric Wrench Set (Part No. BT-009500082).