Window manufacturer.
Looking for replacement window grille fasteners, one on the left and the second on the right. White fastener, approx 3/4 inch vertical (when installed in window) and 1/2 inch horizontal. Portion of fastener that slides into the window is 1/4 inch in length, 1/8 to 3/16 in diameter and has a clear plastic sleeve that resides in the window to hold the fastener (see image IMG_1316 to the right of the fastener, around "4" on the scale).