Kato USA Model Train Products V16 UNITRACK Japanese Packaging Version Double Track Outer Loop Set Contains Super elevated Curves for realistic banked motion (radius 17 5/8" - 19") Designed to create an outer set of loops for the V11 Best to create an outside set of loops for the V11 Set; The V16 Set can be equipped with Double Track Catenary Poles 23-061 (sold separately) Easy to use assorted track set in a box Reliable and easy-to-use UNITRACK snap track system makes setting up both temporary and permanent layouts a snap