This scene opens at the end of Part 1 with Jacob Stax asking Michael about what went on when he went into the exam room. Michael is not telling him details, but assuring him it will all be fine and he will like it. Just then Sean walks into the waiting room and asks for Jacob to come to the back with him. Once inside the exam room, Sean explains that he will be getting penis measurements for the Twins Study and for him to take his pants off. Once Sean Harding gets the flaccid measurement he tells Jacob that it appears he might be a little larger than his twin brother and they so far He and Michael have the biggest penis in the study. Jacob measures about ½ inch larger than his brother when fully hard and it is interesting that he is circumcised but Michael is not. He explains that it because of something that happened when they were born and then Sean continues to pleasure Jacob with his eager mouth sucking his big cock. He deep throats Jacob to the hilt and then Jacob sucks Sean for a little while before bending Sean over the table. Jacob's cock goes balls deep into Sean's eager ass as he fucks him bent over from behind. Sean then gets on his back on the exam table and Jacob fucks the cum out of him. Sean then gets the container to collect Jacob's sperm and has him jack off into the container. He then compares both their samples and let's Jacob know he ejaculated more than Michael. Enjoy!