Hospital-grade Suction: The max suction value reaches to 338mmHg, which ensures pretty decent output. Note: Please reach your Maximum Comfort Vaccum for more milk. You can switch to a suitable suction level based on the usual breast milk output and pain tolerance. Upgraded Mode Choice: It has 4 modes and 9 suction levels and naturally mimics your little one's feeding. The LED screen clearly displays the suction mode, suction level, and battery level. The "dual-frequency" mode helps inverted and flat nipples to pump smoothly. More Sizes for Most Moms: The set includes flange inserts for sizes 19mm, 21mm, and 24mm. The pump itself is 28mm. Note: Moms can find the appropriate flange size by the "measure card" in the package. More Hidden & Comfortable: The wearable breast pump is unnoticed in the bra. It is only 240g, not bulky at all. That gives moms all-around comfort. Smaller Size, Stronger Suction! Safe Enough: Made of BPA-free food-grade silicone, safe for both moms and babies. The anti-backflow design and sealing system prevents breast milk from leakage. The capacity is up to 150ml/5oz, and the optimal collection volume is 120ml/4oz One Charge for One Day: The hands-free breast pump can be fully charged in 2 hours for 120 minutes (4-5 sessions) usage. 1100mAh battery. USB charging. Effortlessly Pump: The electric breast pump is equipped with a memory function. Even though there is no timer on the LED display, the "30 mins timer shutdown" function will be a great addition. Warm Tips: The product description shows many instructions about how to use the P10 breast pump correctly. Once get past of the learning curve, you will find P10 is fairly helpful for breast pumping.