Your search for: Part groups, Components, Profiles without running track/guide track, Joint profile returned 2 hits.
24170 - Connector connecting profile, bottom left/top right, 500 mm (1' 7 11/16''), aluminum, anodized, 500 mm
24171 - Connector connecting profile, bottom right/top left, 500 mm (1' 7 11/16''), aluminum, anodized, 500 mm