Accessories for extending thumb turn cylinders
All Viro thumb turn cylinders (700, 900, New Euro-Pro and Viro Palladium series) are easy to extend on the thumb turn side to make them suitable for fitting to especially thick doors (e.g. armoured doors, fire doors, etc.).
The chromed steel extension, supplied with a grub screw, is fitted as follows: the end with the bigger diameter is fitted to the shaft which usually takes the thumb turn; the other end, with the thumb turn removed, can be machined to the length required and fitted with one of the thumb turns shown in the table.