The radial foil bearing for surrounding and supporting a rotary shaft includes a cylindrical top foil disposed so as to face the rotary shaft, a back foil disposed at a radially outer side of the top foil, and a cylindrical bearing housing accommodating the top foil and the back foil. The kit includes a planar barrier and a first member having a first support structure to movably support the barrier and a first attachment mechanism to secure the first support structure at a first side of the ladder. An overlapping locking mechanism locks the first housing portion to the second housing portion in a first direction when the first housing portion is moved relative to the second housing portion in a second direction. A cutout is formed in a section of one of the outer corners of the outer sleeve to expose at least a portion of a corner of the inner corner. The methods of derivatization include electrochemical induced reactions, thermally induced reactions, and photochemically induced reactions.