Thanks for your reply , Angel . As your advice , it's seems the besy way to checking their sex is by sexing probe . In truth , I know how to use sexing proble to make out snake sex and have much exprence on other species , such as boas , Therefore , the problem of sexing probe use of mine is that different species has their different dipth of their tail while I am checking their sex . For example , I have checked an ETB sex 2 months ago , the dipth of the boa is quite deep and it's seems the ETB is a male boa . It's makes my friends and I wondered that we mistaken the ETB was a male . After we talked about this with a exprence herp importer , he said in truth the ETB is a female . So , as different species has their different dipth of their tail for making out their sex . This problem will never happend while I am checking other species who has longer tail and more easily to sexing out . Bloods has shorter tail and I think it's more difficult than other simple species . Do you know the dipth standard of bloods while I am checking their sex ? thanks . 
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3.5.0 Boa constrcitor
1.0.0 Morelia amethistina
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0.1.0 Brachypelma emilia
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