The gloves, cuffs and the elastic end of the jacket are not made of waterproof fabric. Only the main body is.
For the exterior body of the jacket, we are using waterproof fabric. While the fabric is indeed waterproof, the stitching along the seams may also risk the chance of, but very minimal, water sipping through. However, you can be assured that your belongings in the jacket will remain dry, even when you get caught in a heavy rain. This has been tested and proven!