LEGO Red Hinge 1 x 2 Locking with Towball Socket (30396 / 51482)

LEGO Red Hinge 1 x 2 Locking with Towball Socket has been used in at least 10 LEGO sets over the past 25 years, since it was first used in 1999. You can also find this part in at least 7 other colors. It has a design ID of 30396 which can usually be found molded into the bottom of the part.