Cannot leave home without it! My wife calls this her "secret weapon" in our war on baby terror. This toy functions as a rattle, hand/eye coordination development aid, chew toy, utility hooks, and parental sanity aid. Our baby likes to suck on it while playing, so it's reassuring it's BPA free & Phthalate compliant according to sassybaby website. Of all the toys and rattles, this is by far my 4 months old baby's favorite. Whenever she starts to fuss or cry while we're out, we just jiggle this in front of her, and its soft clacking sound and bouncing colors always calm her down immediately. It's amazing how fascinated she is by this toy! It also has a lot of surface to easily grasp by (one-handed or two) and varied textures (some rings are lumpy, some smooth, some ribbed). You can also interlock the rings into a chain as an alternative form of toy or utility hook (be careful it doesn't become a strangulation hazard). It's also compact enough to fit in a pocket or stroller cup holder. To keep the baby occupied during meals out, we mount it dangled above the baby on the carrier/stroller handle using a looped pacifier strap like Ulubulu Universal Pacifier Clip, Oliver Owl or Velcro strap Velcro Reusable Self-Gripping Cable Ties, 0.5 Inches x 8 Inches Long, Black, 100 Ties per Pack (91140) . If the baby's holding the toy instead, a pacifier strap can also clip to the bib to avoid the toy dropping on the floor. The baby and wife love this toy so much, I just bought another 2 to keep existing the one at home, one in the car, and one in the diaper bag. Of course, your particular baby may have differing tastes, but no fancy projector, sound machine, smartphone app, etc. may save your sanity and public crying baby embarrassment as quickly and easily as this ~$4 toy. Alternatives: Manhattan Toy Winkel is another great toy (baby's second favorite for grasping, staring at, and sucking) and has a soft built-in rattle, but is bulky and not as useful to hush the crying baby. To prevent the baby getting bored of the ring toy, we have her play instead with the Winkel at home. An actual rattle like Bright Starts Rattle and Shake Barbell Rattle is louder, but fails to hold my baby's attention for more than a second, and is very limited in graspable area. It may be good for an older baby, but for now, just sits at home unused. Different vendors have similar toys, some with even more rings, but none seem to have BPA & Phthalate info. Babies love putting everything in their mouths, so we try to seek only toxin-free.