The Core Performance 4x90-3x100 11.25 frame is built to offer stunning quality and performance at the best price. The flat side wall ensures direct power transfer, so that children can make a good push off. The upper, wider part of the frame will improve their stability level. The 11.25" size of this 2in1 inline skate frame allows children to choose between a 3x100 mm or a 4x90 mm setup to respect the rules of the association. This extruded and CNC-machined 6061 aluminum frame not only has the appearance of a professional high range product, it is indeed a top frame that is comfortable for skating.