portion of the implant and the other is placed in the lower inner portion of the implant being nearer to the body of person the final position of these pockets can be decided by the person having the implant and her medical advisors the factors considered could be the wishes of the patient how she wants the final shape of her breasts to be given the size and shape of her natural breasts fig2 shows the steps involved filling the pockets 122 with silicon fig2 a shows an outer pocket 132 whose size could be around 50 milliliters and an inner pocket 134 whose size could be around 20 milliliters there is a valve 133 that allows a substance like silicon to be pumped in to the inner pocket 134 the valve 133 can be sealed after the silicon has been inserted optionally air or other gas could be used to fill the pockets the less flexible silicon layers 104 and 106 hold the shape of the outer rim of the insert fig1 when the pocket 122 is expanded with silicon the silicon layer 108 is more flexible in order to allow the implant to expand upward when the pocket 122 is placed in the lower portion of the implant fig1 fig2 b shows the inner pocket 134 filled and the valve 133 sealed the.