This is LGB's basic, R1 curve, which is the same curved track found in LGB Starter Sets.
30 degree sections means 12 sections will make a 360 degree circle. The R1 curve forms a 1290 mm (50.8 in) diameter circle.
This G Scale Brass Track is the same curve as LGB's old number 1100. Suitable for use indoors and out. Like all LGB track sections, it's ruggedly made with solid brass rails for indoor and outdoor reliability.