Domestos 15 Minute Sink and Pipe Unblocker not only cleans and unblocks pipes at your home in just 15 minutes but its fighting formula kills germs and bacteria and gets rid of their nasty smells. No need for the awkward plungers. You can use this Domestos cleaning product as a general pipe unblocker for blocked showers and slow-draining sinks as it helps to unclog pipes that have become blocked by food scraps. soap scum. hair and more. To use Domestos drain unblocker. simply pour the product down the pipe or drain and leave it to work for the time specified at the back of the bottle. Always rinse pipes and drains thoroughly with hot water after use and say goodbye to nasty smells. germs and to that slow draining sink. blocked pipe or blocked shower in your home with our bath and sink cleaner.