To improve appearance and workability by using smaller screws without exposing their tops.

A rail body 44 of a C shape end view to hold a runner sliding free is applied whole along the back of a concave guide 39 of a rectangle C shape end view. Rims 40, 40 bent inside are processed along both open edges of the guide 39. Inside the guide 39 is put biting a cylinder bottom like washer 34 with a hole 48 in the bottom center to put through a screw 46. On the edge of the washer 34 face reverse to place the guide 39 is processed a notch to catch the rim 40. A stopper 35 is formed to approximately a L shape by a thin sheet like tongue 61 to catch the guide 39 and a thick end 62 processed on its edge to prevent a runner 56 from coming off when put at the end of the rail 44. Putting the washer 34 to catch the guide 39 of the rail body 44 from its end 38 and placing within, it's screwed up to a face 33 by one motion.