Slot blocks specification: package contains 20 pieces 30 series M8 t nut for profiles with 8 mm slot. Profile compatibility: Type B. Size: L x W x H = 16 x 16 x 6 mm. Thread: M8High quality: slot nuts made of high-quality carbon steel have a high hardness and a long service life. Nickel plated ensures good rust resistance.Easy to use: T nut nuts are easy to use and convenient to connect aluminium profiles to other parts. You have to insert these T-slot nuts into the groove before profile assembly, subsequent swivelling or changing is not possible.Industrial use: the sliding nuts are referred to as T-nuts and square nuts and used in automated production lines and assembly workbenches.Widely used: sliding T-nut m8 groove set, which is often used for architecture, woodworking, industrial aluminium frame structures, 3D printers, CNC laser cutters, robotics projects and more.