PLASTIC NUT & BOLT COVER CAPS Plastic cover caps to fit over hexagon nuts and bolt heads.Available in either black or white.The caps fit standard sized metric fasteners;M5 fit 8mm spanner size nuts & bolts.M6 fit 10mm spanner size nuts & bolts.M8 fit 13mm spanner size nuts & bolts.M10 fit 17mm spanner size nuts & bolts.M12 fit 19mm spanner size nuts & bolts.M16 fit 24mm spanner size nuts & bolts.Give an aesthetic finish to any project.Will conceal any sharp edges.Protect against the elements in outdoor applications.Can be packed with grease to help prevent corrosion or seizure.