I can deep throat us to 10 inches with out any problem. Have only done one ten inch cock but didn't have a problem. Most cocks I suck are 6 or 7 but if I am given a bigger one I don't have a problem. I am a singer so I have learned to relax my throat so I can take it all. I can also use my throat muscles and tongue at the same time when the cock is all the way down my throat. I deep throat the cock, then use the swallowing muscles to massage the head and my tongue to massage the shaft at the same time. I can only do that for a few seconds then have to come up for air but I go right back down deep after I get my air. If I didn't have to breathe I could probably keep it down for a long long time. Every guy I've done this too, they always tell me that was the best blow job they have ever gotten. They never have met anyone who could deep throat like me.