Rigid precision coaxial and their associated precision connectors - Part 4: 21 mm rigid precision coaxial line and associated hermaphroditic precision coaxial connector - Characteristic impedance 50 ohm (Type 9/21) - Characteristic impedance 75 ohms (Type 6/21)

Electronic Public Procurement - Innovation guideline - Part 2-1: Framework and models of innovative developments in procurement

Gas heated catering equipment - Part 2-1: Specific requirements - Open burners, wok burners and paella burners

Glass in building - Special basic products - Glass ceramics - Part 2-1: Definitions and general physical and mechanical properties; German and English version prEN 1748-2-1:2017

Explosives for civil uses - Detonators and detonating cord relays - Part 21: Verification of flash-over voltage of electric detonators; German version FprEN 13763-21:2025

Railway applications - Infrastructure- Noise barriers and related devices acting on airborne sound propagation - Non-acoustic performance - Part 2-1: Mechanical performance under dynamic loadings due to passing trains - Resistance to fatigue

Power transformers - Additional European requirements - Part 2-1: Medium power transformer - General requirements; German version EN 50708-2-1:2020

Cable trunking and ducting systems for electrical installations - Part 2-1: Cable trunking systems and cable ducting systems intended for mounting on walls and ceilings (IEC 23A/743/CDV:2015)

Universal Serial Bus interfaces for data and power - Part 2-1: Universal Serial Bus Specification, Revision 2.0 (IEC 100/2331/CDV:2014); English version FprEN 62680-2-1:2014

Rotating electrical machines - Part 2-1: Standard methods for determining losses and efficiency from tests (excluding machines for traction vehicles) (IEC 60034-2-1:2024); German version EN IEC 60034-2-1:2024