If the lock is opened, the key can only be turned up to a certain point (see picture). After that, the cylinder will block and thus the key cannot be removed.
Our 72 aluminum safety padlocks can be purchased with or without key-retaining feature, depending on what they are being used for.
For safety purposes, we strongly recommend to use a key-retaining padlock. Therefore, our 74 plastic-covered safety padlocks are only available with this feature and not without.