Catch turnouts are used in the 'real railway' to prevent collisions by derailing any vehicle which moves towards a route not set for it to pass before it obstructs another track and to derail trains running away in the wrong direction on gradients.
These aren't major problems for model railways, but this model of the catch turnout allows prototype track layouts to be recreated.
Code 124 bullhead rail. Length 210mm (8.25in).
Templates for Peco points are available from the Peco website.