This is a 90 Degree Gusset, Pretty much what you need 20 of, they are relieved for additional clearance yet not enough to adversly effect strength. As always, .25" (1/4) thick.
WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov.
WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov. 