Zinc plated offers corrosion resistance when used indoors, the countersunk head provides a flush finish.
Drill Sizes for Self Tappers :4G = 2.0 5mm - 2. 6mm 6G = 2.3 5mm - 3. 2mm 8G = 2. 9mm - 3. 8mm 10G = 3. 4mm - 4. 5mm 12G = 4. 1mm - 5. 1mm 14G = 4. 8mm - 5. 7mm