You've built an incredible railway line, full of connections that weave back into themselves, you're a master of track engineering, and then it happens; two holes. Something must have gone wrong somewhere but where? Now you don't need to hunt for the error with these handy little double ended pieces and mini add on sections of track. This is a must have collection for any would-be rail-line engineer. SUITABLE FOR CHILDREN AGED 3 YEARS AND UP.