Marshall Tufflex Flat Tee Cover and Base is made of PVC-U. Suitable for Sterling Curve Profile 1 trunking. Sterling Curve Profile 1 is stylish curved perimeter dado and skirting systems that are easy and cost effective to use. Sterling Curve is a sleek data compliant medium sized trunking system with three segregated compartments. The adaptable system has 1 curved data compartments designed to stop clutter, avoid dust traps and to make cleaning easy.