Technical Specifications:• Material: ADC12• Dimensions(Front) : 138.0mmЧ240.0mmЧ35.0mm(5.43"Ч9.45"Ч1.38")• Dimensions(rear) : 120.8mmЧ222.7mmЧ33.0mm (4.76"Ч8.77"Ч1.30")• Wall Opening Dimensions: 120.8mmЧ222.7mmЧ33.0mm• Compatible: VTO3221E-P, VTO6221E-P