Introduction: Objective of the study is to compare heavy elastics and medium elastics at specific time intervals and there force degredation value and comparison of four different brands force degradation value at different intervals of time. Methods: For this study four different brands of elastics are chosen and 10 different size 1/8-inch (2 oz); 1/8-inch (3.5 oz); 3/16-inch (2 oz); 3/16-inch (3.5 oz); 1/4-inch (2 oz); 1/4-inch (3.5 oz); 5/16-inch (2 oz); 5/16-inch (3.5 oz); 3/8-inch (2 oz); and 3/8-inch (3.5 oz). of elastics are chosen randomly for comparison of heavy and medium elastics at different interval of time with force application of 60 gm and the force loss calculated at specific time interval and force degredation value of four brands of elastics .