The set includes 17 x 20mm 90 degree solid cast aluminum corner brackets, 34 x carbon steel galvanized M5 T-slot nuts, 34 x 304 stainless steel M5x8mm Allen bolts, 1 wrench. 2020 series aluminum profile connectors are widely used in the construction of industrial aluminum frame structures, 3D printers, CNC routers, CNC laser cutting machines, CNC plasma cutting machines, 3D engraving machines, machine protection devices, robot projects, DIY racing simulators, fish tank racks, home improvement brackets, etc. We will provide you with excellent after-sales service and quality assurance, if you have any problems after purchasing our products, please feel free to contact us.