SLOT: 8mm for all applicable size except MD-6.5,MD-6.7,MD-7,MD-8 in 10mm.(100mm in high) Material: High impact,self-extinguishing,warp-proof P.V.C.(Polyvinyl chloride) Color: Grey. Tested to UL file E97527 Features parallel holes on both sidewalls to facilate cutting in wire application. Special color, size, length upon request of reasonable quantity.