Building material or admixture for cement, mortar or waterproofing works — check application on the label Practical DIY construction item Check content (kg/L), color and application in the product name These self-drilling flat head screws from Gyproc are made of hot-dip galvanized steel and have a length of 13mm The screws are suitable for Order no GYTEKSDHZ · EAN 5413218563093 Available via at Brico Harput.