4-oz Whirl-Pak Write-On Bags (Box of 500) - Durable, Leak-Proof Sampling Bags for Food, Environmental & Lab Testing | Perfect for Scientific Research, Food Safety & Sample Collection

Write-On Whirl-Pak bags make sample identification easy. Designed with a white write-on strip that can be written on with an ordinary ballpoint pen, pencil, or felt-tip marker with no smearing. Ideal for milk, water, and food sampling. To assist in volume control, the top of the white strip can also be used as a fill line (all fill lines are approximate).