This document specifies technical characteristics and strength requirements for fork arm extensions and telescopic fork arms for industrial trucks. It applies to fork arm extensions and telescopic fork arms, as defined in ISO 5053‑2, designed for use on industrial trucks and stacking lift trucks, as defined in ISO 5053‑1, having fork arm carriers and, in the case of fork arm extensions, fork arms conforming to ISO 2330. This document does not apply to integral transverse telescopic fork devices or scissor-action reach devices.