Marlow Excel R8 This new rope within the Excel range compliments the existing fusion family of products, using a Dyneema® bio-based Dyneema SK78 core but with an 8 plait cover, blended from Technora® aramid and polyester. Available in 4mm and 5mm diameters where it excels as a halyard working on cleats, and 7mm and 8mm where it works as a high performance sheet performing well in ratchet blocks.