Connection unit with LC-D (SM) coupling on mounting rail TH35 according to DIN EN 60715, guide sleeve made of zirconium oxide ceramic (ZrO2) slotted for single-mode applications, guide sleeve made of metal (ZrO2) slotted for multi-mode applications, the width of 1TE enables the installation of up to 12 devices in a standard electrical distributor, plug direction vertical, 90° to the mounting rail, variants: SM, MM