HORNBYHobby Train Tracks - R8262 Double 4th Radius Curve, 45-Degree Track Pieces - Small Scale Model Accessories for Train, Electric Railroad Supplies with HO/OO Gauge Compatibility, curved Tracks

Apparently curves are measured from the centre of a circle to the middle of the arc. Don't expect the track to measure 572mm. It's far less at 445mm. Very misleading as it isn't explained in the description.

just what I needed