Review on Black Reclosable Resealable Inch Zipper Packaging & Shipping Supplies by Aaron Urena

I bought them for an unusual purpose. I need to periodically test photocells that turn on the building's exterior lights. I needed completely opaque black bags to "trick" the sensor into believing it was dark outside when there was actually no sun to turn on the ambient light. These packages are completely opaque and do exactly what I need. They work for anything that might be sensitive to light. Well packaged and arrived on time.