Do NOT use standard chalk: The dust generated by traditional chalk will quickly accumulate inside the inner grooved bezels (over the IR filter strips), completely blocking the optical signals and causing total touch failure. Always use dedicated water-based whiteboard markers or passive styluses.

Bezel Cleaning Method: Periodically run a dry, flat microfiber cloth along the inner channels of the frame to clear away accumulated dust, marker residue, or fibers. Never spray water or liquid cleaners directly into the recessed grooves, as fluid ingress can damage the internal optoelectronic components.