Infant car seats are the category where parents often spend the most time second-guessing themselves, and both of these are at the premium end for good reason. The Nuna PIPA Lite RX is the lightest infant car seat available at 5.3 lbs for the shell, paired with the RELX base that installs in under 60 seconds once positioned. The Clek Liing is heavier but uses a steel anti-rebound bar for superior crash protection and fits infants up to 35 lbs — significantly longer useful life than most competitors. Both meet or exceed FMVSS 213. Neither is a bad seat.

Specs Comparison

Safety Certifications and Crash Performance

Both seats meet FMVSS 213, the federal standard all car seats must pass. The Clek Liing goes further: it uses a steel anti-rebound bar that contacts the back of the vehicle seat during a rear-facing crash, absorbing energy before it reaches the child. This is the same technology used in European seats that are tested to stricter standards. Independent crash testing by the Insurance Institute for Highway Safety (IIHS) has consistently rated Clek seats highly.

The Nuna PIPA Lite RX has its own safety credentials — it's certified to FMVSS 213 and JPMA, and uses Dream Drape fabric that passes flame retardant requirements without the chemical treatments found on other seats. Nuna specifically markets its FR-free fabric as a feature for chemical-sensitive families.

Neither seat has been recalled as of early 2026. Both brands have strong safety track records. The Clek's anti-rebound bar is an objectively additional safety feature; the Nuna's lighter construction doesn't compromise the structural integrity of the seat. When choosing between them, you're not choosing between safe and unsafe — you're choosing between two different approaches to exceeding the baseline.

Weight and the Carrier Fatigue Problem

The PIPA Lite RX shell weighs 5.3 lbs. With a newborn in it, you're carrying 12-17 lbs depending on your baby's birth weight. By comparison, most infant seats weigh 8-10 lbs for the shell — the PIPA Lite RX's weight savings are real and meaningful over 12 months of daily carry.

The Clek Liing weighs 9.25 lbs for the shell. With the anti-rebound bar and larger frame that allows the 35 lb weight limit, the mass is justifiable on paper, but if you're carrying it daily into daycare, through airports, or up stairs, the difference from the PIPA Lite RX is felt in your shoulder and forearm over time.

The NUNA RELX base also stands out for one-handed release — you depress the button and the seat releases cleanly. Parents who transfer between multiple vehicles daily report this as a significant quality-of-life improvement over seats that require more force or two hands to release.

Fit Range and Longevity

The Clek Liing accommodates children up to 35 lbs and 32 inches — most children will use it until age 2-2.5, well beyond what typical infant seats allow. The PIPA Lite RX accommodates up to 32 lbs and 32 inches, which is similar but slightly lower on the weight ceiling.

Both seats fit preemies and small newborns comfortably with the infant insert included. The Clek Liing's larger shell means it takes up more vehicle seat footprint — important if you have multiple car seats in a row or a compact vehicle where rear passenger knee room is already tight.

The Nuna PIPA Lite RX shell is compatible with most Nuna, Bugaboo, and YOYO2 strollers via adapters, enabling a travel system without buying a separate stroller seat. The Clek Liing also has stroller adapter compatibility but with a narrower range of popular stroller brands.

Installation and Real-World Use

The NUNA RELX base installs with LATCH — once positioned correctly, the angle indicator confirms proper recline and the tightening mechanism locks cleanly. Certified Child Passenger Safety Technicians (CPSTs) generally consider it one of the easier bases to install correctly, which matters because improper installation is a leading cause of car seat failure.

The Clek Liing's anti-rebound bar requires contact with the back of your vehicle seat — in some vehicles with contoured seat backs or headrests that fold in the way, achieving proper contact requires more positioning work. It's not difficult, but it's an extra step to verify.

For travel: the PIPA Lite RX is FAA-approved for aircraft use. The Clek Liing is also FAA-approved. If you fly frequently with your infant, both work on a plane seat — the PIPA Lite RX's lower weight is an advantage when navigating a jet bridge with a baby and carry-on bags.

Best For

• Nuna PIPA Lite RX Parents who do daily daycare runs, frequent air travel, or are sensitive to chemical flame retardants in fabrics
• Clek Liing Parents who want maximum crash protection credentials and plan to use the seat well into toddlerhood

FAQ