A microfluidic check valve , comprising: a body comprising: a first outer surface ; a second outer surface axially spaced from the first outer surface along a valve axis (C) orthogonal to the first outer surface and the second outer surface ; a first inside surface ; a second inside surface axially spaced from the first inside surface ; and a lateral surface disposed between the first inside surface and the second inside surface and surrounding the valve axis (C), wherein the first inside surface , the second inside surface , and the lateral surface define an internal chamber ; an inlet bore formed through the body from the first outer surface and communicating with the internal chamber ; an outlet bore formed through the body from the second outer surface and communicating with the internal chamber ; a plurality of bosses disposed on the second inside surface , wherein the bosses are spaced from each other, allowing fluid to flow around and between the bosses; and a floating disk disposed in the internal chamber and freely movable between an open position and a closed position in response to a pressure differential between the inlet bore and the outlet bore , wherein: at the open position, the disk contacts the bosses and establishes a fluid flow path from the inlet bore , through the internal chamber including between adjacent bosses , and to the outlet bore ; and at the closed position, the disk contacts the first inside surface and blocks fluid flow from the inlet bore into the internal chamber . a body comprising: a first outer surface ; a second outer surface axially spaced from the first outer surface along a valve axis (C) orthogonal to the first outer surface and the second outer surface ; a first inside surface ; a second inside surface axially spaced from the first inside surface ; and a lateral surface disposed between the first inside surface and the second inside surface and surrounding the valve axis (C), wherein the first inside surface , the second inside surface , and the lateral surface define an internal chamber ; a first outer surface ; a second outer surface axially spaced from the first outer surface along a valve axis (C) orthogonal to the first outer surface and the second outer surface ; a first inside surface ; a second inside surface axially spaced from the first inside surface ; and a lateral surface disposed between the first inside surface and the second inside surface and surrounding the valve axis (C), wherein the first inside surface , the second inside surface , and the lateral surface define an internal chamber ; an inlet bore formed through the body from the first outer surface and communicating with the internal chamber ; an outlet bore formed through the body from the second outer surface and communicating with the internal chamber ; a plurality of bosses disposed on the second inside surface , wherein the bosses are spaced from each other, allowing fluid to flow around and between the bosses; and a floating disk disposed in the internal chamber and freely movable between an open position and a closed position in response to a pressure differential between the inlet bore and the outlet bore , wherein: at the open position, the disk contacts the bosses and establishes a fluid flow path from the inlet bore , through the internal chamber including between adjacent bosses , and to the outlet bore ; and at the closed position, the disk contacts the first inside surface and blocks fluid flow from the inlet bore into the internal chamber . <EOS>