RubberGum is an innovation from Insignia to make difficult jobs more simple. A specialised fixing seal primarily designed for showers, RubberGum is a silicone alternative to create a watertight seal along horizontal joints. The uses for RubberGum extend far beyond shower cabins being used for a wide variety of items such as toilets, basins, and even the kitchen sink.
On a handy to use roll, RubberGum keeps fresh and can be reused at a later date. A Blu-tack style substance, you can mould RubberGum into the shape you desire. Not only this but once applied you can trim away the excess to leave a neat finish.
You can find a basic tutorial video for using RubberGum here.