This offer is for 1 pack of 8pcs edging for our heavy duty interlocking rubber mats. These edges are for use exclusively with our interlocking rubber mats. - Simply use as is for a straight edge. - If need to use for corner, turn edge over and cut along line where indicated. - Gives a perfect straight edge finish with a bevelled slope to mats. - To calculate how many boxes required please take the number of mats ordered and work out how you will configure them. - Then count number of outside edges. This will be the total number of edges required. Divide this number by 8 and this will be the number of packs you need.