Abstract: A one piece plastic molded hollow armature is shown for a vehicle seat headrest which is formed with two halves. Each half is formed with a wall having a concave inner surface and corresponding convex outer surface and a peripheral edge. At a linear portion of the edges of each half, the halves are joined together by a flexible web forming a hinge. The two halves are rotated about a flexible web to close the armature upon a headrest support post and are sealed together in the closed position. Afterwhich, a foam padding is molded around the armature through a pour in place molding operation and covered with an upholstery member. A plurality of posts extend from one armature half through apertures in the other half. Once the armature is closed, it is permanently sealed by heat staking the posts to form enlarged rivet heads.