The complete set in detail

ZB65II
Sc. No. 658II
Holstentor at Lübeck : Watermark 'multiple letters', extended roadway - 1 Mk. ; green

ZB66II
Sc. No. 659II
Holstentor at Lübeck : Watermark 'multiple letters', extended roadway - 2 Mk. ; violet

ZB67II
Sc. No. 660II
Holstentor at Lübeck : Watermark 'multiple letters', extended roadway - 3 Mk. ; lilac-pink

ZB68II
Sc. No. 661II
Holstentor at Lübeck : Watermark 'multiple letters', extended roadway - 5 Mk. ; blue