Lightweight collapsible stool

A collapsible stool or chair comprising:

• a seat base member;
• a seating surface member collapsible between an open, extended position configured to provide a seating surface, and a collapsed, closed position, the seat surface member including:
• a central seating surface member fixed to the seat base member and defining an outer perimeter, and
• a pair of oppositely disposed and generally u-shaped seating surface members pivotally secured to the seat base member,
• wherein, each of the generally u-shaped seating surface members include a pair of leg portions extending from a base portion thereof, each of the u-shaped seating surface members having an inward directed perimeter thereof, a portion of each inward directed perimeter having a shape that substantially complementarily corresponds to a shape of a portion of the outer perimeter of the central seating surface member;
• wherein, each of the leg portions include a hinge assembly secured proximate terminal ends thereof and to the seat base member such that each oppositely disposed and generally u-shaped seating surface member is pivotal between the open, extended position, and the collapsed, closed position;
• wherein, when pivoted to the open, extended position, the inward directed perimeter of each of the pair of generally u-shaped seating surface members define a recess that substantially complementarily bounds and receives the outer perimeter of the central seating surface member therein;
• a central support member including a telescoping piston member configured to adjust a height of the seating surface member;
• and,
• at least three leg members, each pivotal between an open, extended position, and a closed, collapsed position;
• wherein the seat base member includes a socket configured to connect the seat base member to the central support member including the telescoping piston member configured to adjust a height of the seating surface member, the central support member including an adjusting lever configured to adjust a height of the seating surface member;
• wherein the central support member includes a cylindrical collar having a cylindrical cavity configured to receive and secure the telescoping piston member therein;
• and,
• wherein the cylindrical collar comprises at least two mating members detachable securable to one another, each of the mating members including at least one tapered structural support rib on an inner surface thereof such that when the at least two mating members are secured to one another for purposes of receiving and securing the telescoping piston member therein, a bias is applied by the tapered ribs to the telescoping piston member such that the piston member is frictionally secured within the cavity.