Both are all-in-one 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.
Spec
Nuna EXEC
Evenflo Symphony DLX
Stage
All-in-one
All-in-one
Narrow (3-across)
–
–
Extended rear-facing
✓
✓
FAA-approved
✓
✓
Lightweight / travel
–
–
How they differ
both list the same documented features for the all-in-one stage — the choice comes down to brand, price and your vehicle's fit (check both manuals)
Published limits
Mode
Nuna EXEC
Evenflo Symphony DLX
Rear-facing
5–50 lb
5–40 lb · 19–40 in
Forward-facing harness
25–65 lb
22–65 lb · 28–50 in
Booster (with back)
40–120 lb · 4+ yrs
40–110 lb · 44–57 in · 4+ yrs
Useful life
10 yrs from manufacture
—
Nuna EXEC: All-in-one (rear-facing → forward-facing harness → high-back booster; no backless mode found in manual). Manual gives ONE overall height ceiling for the whole seat — 57″ (145 cm) or less — not split by mode. Forward-facing recommended at 2 years or older; booster at 4 years or older. Do not use if more than 10 years old (printed number, per manual).
Evenflo Symphony DLX: All-in-one (rear-facing → forward-facing harness → high-back booster; no backless mode found in manual — manual: Evenflo Symphony All-in-One / Symphony DLX). Forward-facing also requires at least 2 years old (printed manual requirement, not just weight/height). Useful life is set by the expiration date on the manufacture label (no printed number of years).
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 2026-07-16.
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FAQ
What's the difference between the Nuna EXEC and the Evenflo Symphony DLX? The Nuna EXEC is extended rear-facing, FAA-approved for aircraft; the Evenflo Symphony DLX is extended rear-facing, FAA-approved for aircraft. Both are all-in-one car seats.
Which is right for my car and child, the Nuna EXEC or the Evenflo Symphony DLX? 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: