large fitting needs temporary internal bracing during handling temporary support handling protection large fitting internal brace temporary bracing shipping brace plenum transition racks collapses preserve approved transport or temporary bracing until the fitting is supported and ready for installation. large transitions, plenums, and fittings can rack or collapse when moved without enough stiffness. this large transition has internal shipping braces and the open end racks when moved. do they stay until it is supported in place?