For System Design. The rocker is plugged onto the 1-way button module. To be completed with: Basic button module, 1-way System Design MEG5110-60.. Comfort button module, 1-way System Design MEG5111-60.. Wiser button module, 1-way System Design MEG5113-60.. Extension Plus, 1-way System Design MEG5119-60.. Material: Brilliant thermoplastic. Color: lotus white.