Column Protection System Guard Column Holder for EC 4 x 2 mm and 4 x 3 mm guard columns consisting of: 1 x Guard column holder 2 x Capillaries (ID 0.12 mm) 3 x Ferrules (for HPLC columns with particle size > 2 µm) 3 x Ferrules (for HPLC columns with particle size < 2 µm) 2 x Wrenches (wrench size: 12 and 14 mm) 1 x User manual