This SAE Aerospace Standard (AS) covers high strength thin wall (commercial) metric sockets, universal metric sockets, metric box wrenches and metric torque adaptors which possess the strength, clearances, and internal wrenching design so configured that, when mated with 12 point fasteners conforming to the requirement of ISO 4095, they shall transmit torque to the fastener without bearing on the outer 5% of the fastener's wrenching points. This standard provides additional requirements beyond ASME B107.100 and B107.5M appropriate for aerospace use. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes. The dimensional limits of box and combination wrench lengths have been established to provide configuration control for tool storage applications. AS955 supersedes MA4534 and MA4535.