Ezlok Fire Brigade FB4 Reversible Slam Lock is a 4-lever slam lock that the fire brigade and emergency services have used for many years. The FB4 slam locks are normally used to secure doors to dry risers and areas where the fire brigade and emergency services would require access. The fire-brigade slam locks do not come supplied with keys. ReversibleThe only part of this product that is reversible is the latch. Because the product is reversible, the product can be used for both inward- & outward- opening doors. When the product is reversed, the key will have to be put in upside-down in the keyhole however, it will still work fine.