A flexible bag and attachment mechanism is provided that may be used in a variety of applications where it is desirable to attach a flexible bag to a device or machine. Some examples of such device may include an insect trap, a grinder, volumetric or weight based filler and liquid dispenser, food or perishable storage, etc. According to one embodiment, the bag portion of the device is disposable and the attachment device is reusable. In one variation a tapered neck is attached to the opening of the bag. The tapered neck connects within a tapered collar of the device by way of a press fitting. The neck is flexible so that it can be deformed to a shape that permits it to enter into the collar, and is resilient so that it can return to its original tapered ring configuration to engage the tapered inner circumference of the collar. The bag may be attached to a dispenser for dispensing material. The dispenser may be in part, a grinder or mixer. The dispenser may be a water or liquid dispenser for filling water bags for transport in a backpack. The bag may be used to contain attractants for an insect trap and/or may be used to contain captured insects.