Sewosy designs and manufactures electromagnetic door holders, electric strikes, locks, access control and power supplies used on fire doors held open as DAS and on emergency exits, from its plant in Haguenau. The company states that its ventouses and bandeaux are conformes à la norme NF S 61-937, the French DAS standard requiring positive-safety release on loss of power, with holding forces ranging from 150 daN to over 500 daN. It is a family-owned business of around thirty people.