1 bag contains 12 pieces of long T-slot nuts for MakerBeamXL. MakerBeamXL measures 15x15mm in diameter. This T-slot nut is the extra long version of the regular T-slot nut XL (art.no. 103295). It is 3 times the length and has three holes (M3). The MakerBeamXL T-slot nut long is made of stainless steel was specially designed to slide into the T-slot grooves of the MakerBeamXL profile. The T-slot nut is great to fasten MakerBeamXL brackets more easily. These T-slot nuts long are NOT compatible with MakerBeam (10x10mm).