  The reflectivity of ultracold neutron (UCN) guides produced with a dedicated
technique called {\sc Replika} has been studied. The guides are made of nickel,
where the surface quality was copied from a glass layer. This results in a
surface roughness smaller than 10 \AA. The reflectivity was measured to be
99.9% or higher. Those guides can be used at present or future UCN sources to
transport UCN over long distances to the respective experiments without
significant losses.
