High stretch, by which we mean 50% stretch.
If your pattern is sized for a medium stretch (25-35%) fabric, you can still use it, but you may need to take the garment in on the side seams after you have tried it on.
Knitwit Stripe Jersey Knit Simplicity is four way stretch, by which we mean the fabric stretches in 2 directions: from selvedge to selvedge and also lengthways.
If your pattern is sized for a two way stretch fabric, you can still use it.
[Spandex is the preferred name of spandex fibre in the US, and it is known in Europe as elastane, and in the UK and Australia as Lycra®. Spandex is actually an anagram of expands.]
95% Viscose/5% Spandex 145cm wide Medium weight – 250gsm