Mastalongset is a hard setting plaster based cement for bedding tape into recessed edges and butt joints. It is also suitable for second coating plasterboard joints, internal and external angles and fastener heads.

Mastalongset has an extended working time of around 65 minutes with a setting time of 80 minutes, making it ideal for mechanical tools. All Siniat jointing and finishing compounds can be used over Mastalongset as a final coat.

This bedding cement mixes to a smooth, creamy consistency by hand or electric mixer, it is very easy to trowel by hand and mechanical tools, and has great body on the trowel and on the hawk. The longer working time reduces frequency of mixes, resulting in more metres covered and less wastage. There is also more than enough time to to obtain good thin edges when feathering and re-trowelling as it does not dry out too fast.