The Spectrum SZ01 together with the SZ02 fauteuils were designed by Martin Visser for Spectrum in the 1950s and 60s as well as the fauteuils SE05, SE06 and SE07. The furniture is named after a simple system where the first letter ( in Dutch) indicates the type of furniture; b (bed)=sofa, s (stoel)=chair, and t (tafel)=table. SE is a chair for the dining room and SZ a chair for the living room. The two digits indicate the model.