5749721-3 is a 28-position vertical receptacle header from the AMPLIMITE .050 Series, designed for high-density D-subminiature connector applications. This connector features through hole tails for PCB mounting and includes latchblocks for secure mating, but does not include rails or boardlocks. The housing is made of thermoplastic with 94V-0 flammability rating in black and is SMT compatible, while contacts are phosphor bronze with duplex gold plating (minimum 0.000030 inch / 0.00076 mm) on the mating end and tin on the solder end. The connector utilizes a compact 0.050 x 0.100 inch (1.27 x 2.54 mm) grid spacing. Common applications include data and device interconnections where high-density, reliable connections are required.