Rib tapes are thin (very thin) strips of decals that ar placed over the ribs of the wings to simulate the stitched seams of the cloth wing covering. Better decal sets for WWI planes include them otherwise you have to buy extra wing decals and cut your own.
Luckily this set in the Eduard Profipack came with them (decals are made by Cartograph). Of course the "barber pole" decals on the fuselage are also separate strips that have to be lined up.
What fun!
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Doc Wiseman Improvise, Adapt, Overcome. Chance Favors the Prepared Mind. Too Dumb for Opera, too Smart for NASCAR.