nodeko T-Gliders, and you guested it, these are for nodeko T-Rails.
Several of these rails are available, generally called I-Beam curtain tracks.
The nodeko version is a modern take on the traditional curtain track which use what are called runners rather than curtain track gliders.
May also be suitable for other curtain tracks, including the Swish Nylongide.
NOTE sold in quantities of 1, photo for illustration.