A reversible key is a key whose handle (shank) has hollow bores and / or notches arranged identically on both sides. The key has the same features when rotated around its longitudinal axis and can therefore - regardless of which side of the key is facing the lock - be inserted rotated into the key channel of the associated lock cylinder, which is not possible with a normal one-sided notched key . This type of key is often used for car keys and is the standard in Switzerland.
The invention of the reversible key with countersunk hole in 1934 by Fritz Schori made KABA (KAssen-BAuer) locks a successful product.
- Lorenz Häfliger: Contributions of Switzerland to technology: Swiss inventions of international importance. Festschrift for the anniversary of 700 years of the Swiss Confederation. Olynthus, Oberbözberg 1991.