Attributes . Kit Includes: Single Strut 1-5/8" x 1-5/8" and 1-5/8" x 7/8". Threaded Rod: 1/4" 3/8" 1/2"5/8". Additional Dies: Back to Back Strut: 1-5/8" x 3-1/4". Cooper B-Line 4D21: 2-1/8" x 1-1/16". Cooper B-Line 4D22: 2-1/8" x 2-1/8" . Names