Both are booster car seats — here are their published manufacturer specs side by side.
This compares published manufacturer specs — not safety or fit advice. The seat's manual, your vehicle's manual, NHTSA's tools and a certified CPST are the fit-and-safety authority; always check them before installing.
As an Amazon Associate we earn from qualifying purchases, at no extra cost to you. Weight ranges are the manufacturer's published limits across all modes.
How they differ
the Clek Oobr is listed narrow (roughly ≤17″) for fitting three across a back seat; the Evenflo Big Kid isn't listed narrow
the Evenflo Big Kid is the lighter, more travel-friendly model
Published limits
Mode
Clek Oobr
Evenflo Big Kid
Booster (with back)
40–100 lb · 43.3–57 in · 4+ yrs
40–110 lb · 40–57 in · 4+ yrs
Booster (backless)
40–100 lb · 43.3–57 in
40–110 lb · 40–57 in · 4+ yrs
Useful life
9 yrs from manufacture
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Clek Oobr: Belt-positioning booster convertible between full-back and backless mode. Current (July 2025) revision prints identical 43.3-57in/40-100lb/4+yr limits for both modes (an older April 2017 revision bundled in the same PDF showed a slightly lower backless minimum height of 38in; used the current printing).
Evenflo Big Kid: Belt-positioning booster convertible between high-back and backless mode (identical weight/height/age requirements printed for both — manual: Evenflo Big Kid/Big Kid LX Booster Seat). Not a harnessed seat. Useful life is set by the expiration date on the manufacture label (no printed number of years). Note: manufacturer PDF filename/URL says 'us_amp' but the actual document is the Big Kid/Big Kid LX manual (confirmed by title page) — Evenflo's 'Amp' product is a different manual, hosted at a URL confusingly named 'bigkid-backless-booster-car-seat'.
That is the record of the brand — not a verdict on these models. A recall names specific models and manufacture-date ranges, and a seat missing from the record is not "recall-free": check nhtsa.gov/recalls with the model and date of manufacture on your seat's label. Source: NHTSA, retrieved 2026-09-05.
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FAQ
What's the difference between the Clek Oobr and the Evenflo Big Kid? The Clek Oobr is narrow for 3-across; the Evenflo Big Kid is lightweight/travel. Both are booster car seats.
Which fits three across, the Clek Oobr or the Evenflo Big Kid? The Clek Oobr is listed narrow (~≤17″) for 3-across; the Evenflo Big Kid isn't. Three-across fit still depends on your exact vehicle — confirm before buying.
Which is right for my car and child, the Clek Oobr or the Evenflo Big Kid? That depends on your specific vehicle and child — this page compares published manufacturer specs only, not fit or safety. Check the seat manual, your vehicle manual, NHTSA's car-seat finder and ideally a certified CPST before deciding.
Citing these specs? Go ahead — published manufacturer data, last verified 2026-06-11. Copy a ready-made reference: