Blue plastic (nylon) keycap, simply applicable by getting it stuck in most of Viro keys:
they renew the keys design;
the retailer may request one side of the key customised with its own logo and/or its contact details, to
stand out and to foster customers’ loyalty;
neutral cover available (without Viro brand), that can be customised on request on both sides of the cover;
Surcharge for each side with printed customisation.