"Bought this product as it fitted perfectly to my needs plus it is produced by a tried and tested name all be it with other products. However I found it almost impossible to get any real volume of material out of the tube. I put so much pressure on one mastic gun it bent the handle. Have made sure the tube and nozzle are clear but it appears the sandy texture prevents it passing through a standard 310 ml tube nozzle. Will be returning the product for a refund."