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

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; German and English version prEN 16727-2-1:2025

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

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

Environmental testing - Part 2-1: Tests - Test A: Cold (IEC 104/1046/CDV:2024); German and English version prEN IEC 60068-2-1:2024

Primary batteries - Part 2-1: Physical and electrical specifications of batteries with aqueous electrolyte