Most manufacturers refer to miniature ball screws as those with a diameter smaller than 16 mm, while others include 16 mm screws in this definition.
STEINMEYER MINIATURE BALL SCREWS
High Quality China Ball Screws And Miniature Ball Screws
KSS Superdrive — Reliance Precision Australia
Ball screws for smooth linear motion
Ball screws - MPS Micro Precision Systems AG
Miniature Ball Screws
KSS company limited English-language site
Precise linear movements thanks to miniature ball screw assemblies
Miniature Ball Screws - August Steinmeyer GmbH & Co. KG