SC. The 2430 Digital Lock (No Holdback) from Lockey is a stylish mechanical unit with reversible handing. When used with the relevant intumescent pack (L27394), it is rated as suitable for use on fire doors to BS EN 1634. With 8,191 possible PIN combinations of 4 to 7 digits and a 60mm backset, it is also weather resistant and suitable for external applications.. Reversible handing. Weather resistant. Digital keypad for entry and handle turn for exit. Codes between 4 and 7 digits