Buck Baits Estrus Max Certified Peak Estrogen Brown 4 oz.. Buck Baits uses scientifically advanced urine collection and processing techniques to arrive at the certified peak estrogen levels.Biologically derived urines from does are the source of estrogen for most natural scents including doe urine. Buck Baits uses urine collected from does in heat and doe a urine sample for testing.Biologically Engineered to peak estrogen levelsDoe urine is collected and processedBiologically Engineered to peak estrogen levelsDoes not use doe a urine samplerDoes not use urine samplers Certified to peak estrogen levels. All urine is tested for heavy metals including lead aluminum copper anti-estrus hormones. Package Contents: Buck Baits Estrus Max Certified Peak Estrogen Once the does are in the peak of heat the urine is collected and sampled to certify for peak estrogen levels. Once at the peak the urine is bottled as estrus Max