An apparatus having a first portion including a first front wall, a first rear wall, and a bottom wall integrally coupled to the first front wall and the first rear wall, and pivotal pin structures integrally coupled to and extending from the first rear wall. The apparatus includes a second portion having a second front wall, a second rear wall, and a top wall integrally coupled to the second front wall and the second rear wall, and pin holders integrally coupled to and extending from the second rear wall and at an offset angle with reference to the top wall. The pivotal pin structure includes a base support connected to the first rear wall and a shaft connected to the base support, and the pin holder defines an opening sized and shaped to accept the shaft. The first and second portions are sized and shaped to be pivotally movable between open and closed configurations.