Acrylic-based mastic for sealing gaps in connection to skirting boards and thresholds. Bona Gap Master is a silicon-free, acrylic-based mastic for sealing gaps towards skirting boards and thresholds. The mastic is available in 15 different colours and can be finished with all Bona lacquers when dry. Its material is permanently elastic (15 % maximum movement tolerance), and it is solvent-free and odourless. It can also be used to repair damages and fill gaps and cracks in a wood floor. Material: Acrylate Drying time: approx. 18-24 hrs. Full hardness is achieved after approx. 2-3 days depending on climate and size of gap. Consumption: Depends on size of the gap.