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Hydrogen Technologies Standards form the basic framework for market ramp-up
More information
Climate change Standards and specifications support climate targets
More information
Smart Farming Standards and specifications are drivers for the digitalization of agriculture
More information

Standards [CURRENT]

BS A 401-420
Specification for screws, pan and 100° countersunk head, hexalobular drive recess (unified threads below 1/4 inch) in various materials

Edition 2015-10-31

Original language English

Price from 313.50 €

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DIN SPEC

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Terminology

Hydrogen Technologies Standards form the basic framework for market ramp-up

Climate change Standards and specifications support climate targets

Smart Farming Standards and specifications are drivers for the digitalization of agriculture

BS A 401-420 Specification for screws, pan and 100° countersunk head, hexalobular drive recess (unified threads below 1/4 inch) in various materials

Want to learn more?

BS A 401-420
Specification for screws, pan and 100° countersunk head, hexalobular drive recess (unified threads below 1/4 inch) in various materials