This penetrating water based, co-polymer sealant is formulated to be so thin that it finds its way INSIDE fine cracks by capillary action, and sets to a clear flexible seal. Compatible with wood, rubber, glass, metals, perspex, glass fibre, ceramics, concrete, brickwork and old sealants. Will not disolve polystyrene. Uses about the house Leaks in flat roofs and conservatories; cracks in slates; brickwork & concrete. Penetrates and seals ageing joinery eg old front doors, window casements & frames; window putty and sills; stained glass windows; rubber seals. Kitchen worktop joints and around inset sinks & hobs. Dripping plug waste surrounds. Shower trays & cracked vases, ceramics, fish tanks etc. Uses for the caravan Leaks around windows, metal and rubber trim & fittings; rivets; gullies & skylights. Uses for the boat Leaking windows, portlights, decks, coachroofs, deck houses etc., cracked planks, centreboard casings and around all deck fittings.