Ronseal Medium wood filler 100g. This wood filler from Ronseal has been specially designed for general or minor repairs to wood on window frames screw/nail holes cracks & skirting boards around the internal & external areas of your home. It provides tough & durable repairs to any wood it's used on. It's best applied with a filling knife or spreader & can be stained varnished or painted once dried. It's sandable heat resistant & drip resistant too.