zangra says

This door handle in black Limoges porcelain is entirely handcrafted. The production method used for manufacturing these door handles has remained unchanged for nearly a century
The quoted price is for a set of 2 door handles, i.e. for 1 door. Dimensions porcelain plate: 19,5cm x 4cm. Distance between screws: 16,5cm.
2 porcelain keyhole plates and the necessary screws are included.
The porcelain is pressed into a metal mould and heated to 1400°C.

The door spindle is 7 mm wide for France and 8 mm wide for Belgium and the Netherlands

Technical description