PURPOSE: To reduce the number of parts and simplify the mounting work, by integrally molding an inner and an outer covers.

CONSTITUTION: Flanges 23, 23 are protruded from the fronts of an inner and an outer covers 21, 22 of triangular side shape so that the flanges are engaged on the brims of the glass runner fitting groove 1a of an upper sash 1. The inner and the outer covers 21, 22 are integrally molded together with a vertical wall 24 on the rear sections of the covers so that a prescribed distance is defined between the covers. Protrusions 25, 25 are provided on the insides of the rears of the inner and the outer covers 21, 22. A glass runner holder 26 is composed of the vertical wall 24 and the rear sections of the inner and the outer covers 21, 22.