An ostomy bag collects body waste from a stoma opening in your abdomen. You should know how to apply and remove an ostomy bag to prevent complications. The bag is constructed with nonwoven material on both the back and front, providing softness, sweat absorption, and minimal friction sound. With a cutting size of 15-38mm, the colostomy bag ensures good adhesion and is suitable for all adults. You may need a stoma to remove wastes after colon or bladder surgery. Learn what happens when you get a stoma, and how to adjust to life with your new pouch. An ostomy bag is a pouch that collects urine or stool through an opening in the abdomen called a stoma. Ostomy bags can be temporary or permanent, depending on the person's health condition and medical needs.