Xtrus Certified Doe 'N Synthetic 4 oz. Doe Estrous Scent by Buck Bomb®. Buck Bomb XTRUS is unlike any other deer urine that's ever been available. XTRUS is the first and only estrus whitetail doe urine that is tested and certified to contain estrogen in the urine. Each batch is lab-tested and certified for maximum estrogen levels before ever going into a container. What does all this mean? Each batch of XTRUS has hard proof that it not only contains estrogen, but extreme levels of estrogen for maximum attraction power for bucks during the rut. The easy-to-use dropper bottle contains scent that is perfect for use with the Buck Bomb Detonator retractable scent wick (sold separately) or with the included spike wicks.