Aluminum, qq-a-250/8, comp 5052-h32; 0.0625 in. Thk, 1.4375 in. Lg o/a, 1.0625 in. W; 0.6562 in. W by 0.5625 in. Deep and centered cutaway along lg; 2 elongated holes 0.1719 in. W by 0.2969 in. Lg along width 0.5625 in. C to c 0.2500 in. From edge to centers