Concealable ski binding

In combination, a concealable ski binding and a ski boot, said ski boot having a sole, said sole defining a lower face, said lower face having formed thereon a recess having at least one end and at least one other end, said at least one end of said recess having formed thereon at least one first abutment, said at least one other end of said recess having formed thereon at least one second abutment, said concealable ski binding comprising at least one body, at least one fixed coupling element, at least one movable coupling element, at least one first piston, at least one fluid containing chamber, at least one tank chamber, and at least one operating piston, said body being fixable to a ski and removably accommodatable in said recess, said fixed coupling element being defined on said body and adapted for engagement with said first abutment, said movable coupling element being supported by said body, adapted for releasable engagement relationship with said second abutment, and connected to said first piston, said first piston being sealingly movable in said fluid containing chamber, said fluid containing chamber communicating with said tank chamber, said operating piston being sealingly movable in said tank chamber and adapted for protruding from said body, said operating piston being further adapted to be pushed into said tank chamber by at least a portion of said recess upon application of said ski boot to said concealable ski binding, to feed fluid from said tank chamber into said fluid containing chamber with consequent motion of said movable coupling element, for causing said movable coupling to engage with said second abutment.