Clear up clogged household drain pipes with this Buster Plughole Block Preventer. It features a unique Diactive foam that expands to fill the entire pipe, deep cleaning to prevent build­up of gunge and trapped debris in plugholes, pipes and overflows for up to eight doses. Suitable for kitchen and bathroom sinks, showers and baths. Size: 2 x 250ml (500ml). Usage: Simply squirt into plughole or overflow until foam fills the pipe. Also around the sink, bath or shower surfaces. Leave to work for 30 minutes. Flush with hot water. Always replace the cap after each use. Suitable for use with waste disposal units.