A single piece sheet metal clip including a trim engaging part and a mounting part extending or extendable from the trim engaging part at a right angle, the trim engaging part having a limited height when the clip is tilted from a vertical portion and a height greater than the limited height when upright whereby the trim engaging part may be inserted between opposed channels on a rear side of a trim strip and upper and lower edges are trapped in a respective channel when rotated from the tilted position to an upright position, the trim engaging part having an integral element resiliently deflected in a channel when the clip is turned upright, said resilient element releasably locking the clip against a reversal of said movement and thereby maintaining the trim engaging part trapped in said channels.