Our Post Mix Rapid Set Cement (20kg) is the perfect solution for quick and easy installation of posts. Just add water to the bag and you are ready to go with no need for any mixing. One bag will give you a square post 10cm (4") with a hole 20cm 8") wide x75cm (30") Deep and sets in 5-10 minutes. Get your posts installed quickly and easily with our Post Mix Rapid Set Cement.