Which self-levelling head do I need for porcelain tiles?

Use the porcelain tile head (84HEADPAVE). It features removable spacer tabs to accommodate tiles of different sizes, and is designed for use with the adjustment key (84KEY) — allowing you to fine-tune the pedestal height without lifting heavy tiles. Simply insert the key from the side and rotate to raise or lower the head. For aluminium joist systems, choose 84HEADOUTDURE; for timber joists, choose 84HEADJOIST.