Finally solder all the solder joints. Specification: Thread Size: M8 x 1.25mm ;Thread Type: UNC ; Width: 14mm/0.55; Height: 7mm/0.27;Material: Carbon steel;Grade: 4.8. Application: Used for pipe furniture, tables and chairs, shelves, vehicles, trolley casters and other threaded connection The measurement allowed error is +/- 0., 3mm. M8 Stainless Steel Rectangular Weld Screw Nut Square Welding Nuts Ss304 Carbon Steel Welding Nuts M8 Square Weld Nuts Plain Steel Weldable Nuts For Welding DIN 928 Pack Of 20 M8 Square Weld Nuts Carbon Steel 10 Pack UNC Thread Second welding a little bit and adjust the verticality of the thread . Specification: Thread Size: M8 x 1.25mm ;Thread Type: UNC ; Width: 14mm/0.55"; Height: 7mm/0.27";Material: Carbon steel;Grade Steps: First clean the welding surface, using sandpaper or steel brush to remove the joint oxide. Specification:Product Name: Square Weld NutsMain Color: Silver ToneMaterial: Carbon SteelThread Size: M8 x 1., 25mmOverall Size: 14 x 14 x 7mm / 0., 55 x 0., 55 x 0., 28(L*W*H)Solder joint height: 1mm / 0., 04Package Content: 10 Pcs x Square Weld Nut