character: this product is a chemical compound extracted from selaginellae herba. it has been highly purified into white powder crystal which can dissolve in water and ethanol but can't dissolve in fat. it is smelless and bitter with the purity of above 99. 95%. the product should be kept in dark and dry place. function: the acting principle of this product: nanc neuron and carbon monoxide enzyme of blood vessel endodermis cells catalyze the composition of carbon monoxide from l-arginine. carbon monoxide stimulates the composition of guanosine which can lead to the relaxation of smooth muscle of penis sponge and penis arteriole. the penis will have an erection when there is blood pouring into penis sponge. thus, this product belongs to 5 type vinpocetine (sildenafil). effects: this product is re-composed by sildenafil which belongs to the derivatives of sildenafil. and its changable forms lg-ms, hplc have been tested by advanced facility and have passed international intellectual property protection policy. it doesn't belong to the protection scope but also doesn't in the forbidden scope of government. absorption: it will be absorbed by intestines and stomach after taking and can take 50% effect in 15-30 minutes, 83% effects in an hour. the effect can prolong to 8-12 hours. this product can be absorbed quickly when taking orally and can reach its peak value in 1-2h. t1/2 is 8-12h. take this product once a day and the effect can prolong to 24-36 hours. there is no obvious accumulation. and the consistency will changed as per the dosage of this product. there is no obvious influence to blood pressure and heart rate when taking this product once a day. the recommended dosage of this product is 120mg/time. harmful reaction: headache, red face, nasal congestion, abnormal eyesight (barrier of distinguishing color in a short time). scope: the one who takes medicine which contains nitrate and which can expand blood vessel can't take this product. and it is not applicable for the one who suffers from blood condensing barrier, active ulcer and retina inflammation. characteristics: the advantage of huanyangjian is that its side effect is small than sildenafil citrate and can't be tested. storage: sealed shelf life: 2-3 years specification: 1kg/20kg/50kg can be delivered (we can supply this product to you according to your requirement).