client from the N-ERGIE Aktiengesellschaft with a functioning window element but also to provide the required proof of mechanical stress, long-term function, impact resistance, sound insulation and condensation [...] protection and an internal pivoting sash for inspection and cleaning work, with a closed pivoting function". Jürg Egli, Head of Property Management at Forster Profile Systems, explains with a grin that this [...] its durability, Forster Profile Systems has subjected the pivoting casement window to a long-term functional test. In the process, the usual test series, which range between 5000 and 20,000 cycles, were exceeded