Abstract
1. Traditional supports of cloth or metallic net on frame
2. Rigid cement conglomerate supports
3. The elastic looms developed by the "Istituto centrale del restauro" (Rome)
4. Rigid support of synthetic resins
4.1. Masonite and rigid foam support on metal frame
4.2. Synthetic foam backings
5. Honeycomb constructions
5.1. Paper Honeycomb Holders
5.2. Aluminum Honeycomb Brackets