I often shoot in low light and had trouble finding my Lowepro flipside zippers. I recently stuck some yellow anti slip tape on my back steps and this lead me to try some on my camera bag zippers. Now my zippers are a lot easier see and feel. I found this at PetaPixel: https://petapixel.com/2016/06/22/quick-tip-upgrade-camera-bag-zippers-just-bucks/