Front panel 3HE/7TE with 12 E2000 couplings, slotted ceramic guide sleeve for single-mode applications, suitable for installation in OpDAT REGpro and OpDAT REG S, powder-coated sheet steel, grey, variants: equipped with 12 E2000 couplings, each blue (OS2) or E2000 APC couplings, each green (OS2)