The 133MX-14 is a moderate height breast tissue expander used in breast reconstruction that is manufactured by Allergan. The "M" means moderate height and the "14" indicates a base width of 14 cm. The manufacturer's suggested fill volume for the 133MX-14 is 600 cc or milliliters. This means that at 600cc, the tissue expander is fully inflated and should have no wrinkles. Tissue expanders are temporary devices designed solely to expand tissues to accommodate the final breast implant. There is no manufacturer's suggested filling range as exists for breast implants. The amount of saline inserted into an expander is determined by the expansion needs of the individual patient. Overfilling is commonly done, if needed, but no maximum limit is set by the manufacturer. If the desired expansion is reached before 600cc is inserted, no more saline is required. Tissue expanders can rupture for no apparent reason just like an automobile tire can have a blowout. Needle sticks during the filling process or during surgery can damage tissue expanders and cause leaking. Tissue expanders are stiff in their construction to withstand needle sticks and expansion. This stiffness can cause wear points between the stiff part of the expander and the softer part of the expander. These wear points can cause rupture in tissue expanders that are left in place for a long period of time. I suggest that you discuss your concerns and your questions with your operating surgeon. He or she will be aware of the specifics of your situation and be able to give you the most accurate information.