Standing Estrous was the first breakthrough; Now, years of development at a leading animal research university, have resulted in an all-new technology: Standing Estrous. It's the next generation estrous -- tested and proven to be 63% more effective -- the highest buck response rate ever tested by Code Blue Scents.Standing Estrous is unlike an other scent because it's collected at the precise time a buck tries to breed. She stands, he attempts to breed, we bottle it. Due to the unique process involved, this is a limited availability estrous, but if you're lucky enough to get a bottle, you'll have the most potent estrous available.