This is a quality set of nylon strings with silver-plated wound basses. In terns of materials, they are like classical guitar strings, but at the appropriate gauges. The first 6 courses are unison and the two diapasons are in octaves. Given the price, they represent excellent value for money.
You might be a purist and want to use gut, or you might like the modern alternative, nylgut, a specially extruded nylon treated to feel and sound like gut (Nigel north uses those.) You will pay a lot more for those.
After WWII, when nylon became commercially available, virtually all guitarists stopped using gut and changed to nylon. The sound is different, but the reliability and durability are orders of magnitude better. You can bet your boots that if nylon had been available in renaissance times, lutenists would have used it.