SYNOVEX ONE Grass (trenbolone and estradiol extended release implant) is a growth promoting implant that is indicated for increased rate of weight gain and improved feed efficiency for up to 200 days in pasture steers and heifers (slaughter, stocker and feeder). Each implant contains 150 mg of trenbolone acetate, 21 mg of estradiol benzoate and consists of 6 pellets.