The surface is smooth, much like the Goodyear hose I have used for many years.
What did surprise me in light of its' pressure capabilities is that it is slightly more flexible in use but the big surprise is that it is noticeably easier to coil in cold weather. Overall I'm very pleased with it.
Product group 110 Inner tube Synthetic temperature resistant rubber Cover Abrasion resistant rubber Temperature min. °C -40 Temperature max. °C 155 Media Oil, Water Reinforcement One braid of compact steel wire Safety factor 2.5:1 Applications/Characteristics This hose is intended for pressure washers where low weight and pliability is required. Available in black, oil resistant rubber for workshops and flush halls; and in blue for sensitive environments.