A combination spring tension rod and mounting bracket assembly easily mounts within a window opening. The spring tension rod includes a pair of elbow-shaped receptacles including a first and second arm defining an angle greater than 90.degree., wherein each first arm is mounted on opposite ends of the rod and the second arm defines a receptacle for a respective mounting bracket. Each of a pair of mounting bracket devices is mounted into the respective receptacle. The spring tension rod is compressed and positioned such that bearing surface portions of the bracket devices extend into the window opening. The spring tension rod is then released and forces the obtusely-oriented bearing surfaces to bear against opposed and facing surfaces of the window opening when installed. The spring force of the spring tension rod retains the rod and brackets in the installed position.