Slidable step for mounting and dismounting a vehicle

A step assembly for mounting or dismounting a vehicle, comprising:

• a tread having a left width portion, a right width portion, a near length portion, and a far length portion;
• a left bracket member engaging the left width portion, the left bracket member further engaging a left pivot assembly;
• a right bracket member engaging the right width portion, the right bracket member further engaging a right pivot assembly;
• the left bracket member secured to a left rail-engaging member, the left rail-engaging member structured so as to enable slidable movement longitudinally along the vehicle of the step assembly along a rail, wherein the left bracket member and left rail-engaging member are in a fixed, non-rotatable relationship with each other;
• the right bracket member secured to a right rail-engaging member, the right rail-engaging member structured so as to enable slidable movement longitudinally along the vehicle of the step assembly along a rail, wherein the right bracket member and right rail-engaging member are in a fixed, non-rotatable relationship with each other;
• and
• at least one handrail-receiving member secured to the left width portion or right width portion for securedly engaging a handrail assembly, wherein the left pivot assembly and right pivot assembly enable the tread portion to rotate along an axis substantially proximal to the far length portion of the tread, and wherein the at least one handrail-receiving member is structured to secure a handrail post.