The C-4 was designed by Trevor Brazile as part of his Relentless line to compliment the Xplosion in hot weather. When it starts getting summer hot out, this rope will impress you as it feels better and better every single run. When its over 85 degrees, ropers will find this rope will hold up and take the hits and feel better as the days roping progresses. The absolute best hot weather rope on the market!