Amazon has a mifold Grab-and-Go Booster Car Seat Sale, $19.19 Free Shipping $25 or with Prime. Expires Soon - Highly rated at 4.2 out of 5 stars.

• COMPACT BOOSTER SEAT – the world’s most compact, backless booster. Designed for kids, aged 4 and up, 40 to 100 lbs, and 40 to 57 inches tall, mifold is more than 10x smaller than a traditional booster, and just as safe.
• PORTABLE BOOSTER SEAT IDEAL FOR TRAVEL – mifold foldable booster fits into a child’s backpack, glove box or parent’s handbag, making it perfect for carpooling, as a travel booster, for ride sharing and much more.
• KEEPS CHILD SECURE – mifold ensures optimal seatbelt fit. Instead of lifting the child up, the grab-and-go car seat adjusts the adult seatbelt by pulling it down to fit the child safely and securely.
• SAFETY TESTED – This kids booster seat meets or exceeds NHTSA standard FMVSS 213 in the USA.(THIS PRODUCT IS ONLY FOR USE IN THE USA and is not the International version, regulated under ECE R44/04)
• CONVENIENT– This travel car seat is easy to use and has won many awards, including a Mom’s Choice and Parents’ Picks Awards. It’s a great choice for older kids, grandparents or for fitting three children in a row.

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