Filltite Ultra-Light Filler quickly make repairs to walls and ceilings in just one application, without sagging or slumping. With a super smooth finish there is no need to sand and it can be overpainted in as little as 15 minutes. Apply straight from the tub with a filling knife to interior and exterior substrates including plaster, plasterboard, wood, concrete, cellular concrete, masonry, roughcast and cement render. Remains flexible once dry and can be painted from 15 minutes.