The LUMN Harness to Booster Car Seat is designed to grow with your child, combining advanced safety, long-term usability, and a modern design that matches big kid style. Engineered with an all-steel frame and premium materials, it transitions seamlessly from a forward-facing harness seat to a belt-positioning booster, delivering comfort, protection, and practicality for every stage. Its slim profile, easy-clean fabrics, and adjustable features make it a smart solution for families looking for durability and everyday convenience.

Why choose the LUMN Harness to Booster Car Seat

Grows with your child from harness to booster
Seamlessly transitions from a 5-point harness to a belt-positioning booster, supporting multiple growth stages with one investment
Advanced safety with reinforced structure
All-steel frame and reinforced belt path provide superior protection and long-lasting durability
Custom comfort with multiple adjustments
Features 10 headrest positions and 9 recline options when tethered for a precise and comfortable fit
Slim design for better vehicle compatibility
Fits 3 across in most mid-sized vehicles, ideal for families needing space optimization
Premium materials with easy maintenance
Wipeable leatherette accents and machine-washable seat pad simplify everyday cleaning
Certified safety and clean materials
FAA approved in harness mode, meets latest impact standards, and made without added fire-retardant chemicals
Designed for long-term use
Up to 10-year lifespan, ensuring extended usability through multiple growth phases

Characteristics / What’s included / Technical specifications

Features

Harness to booster convertible design
5-point no-rethread harness that stows away in booster mode
10-position height-adjustable headrest
9 recline positions in both harness and booster modes when tethered
Bubble-free recline guides for accurate positioning
Slim design fits 3 across in most mid-sized vehicles
Machine-washable seat pad and removable inserts
Pop-out cup holders, removable and hand washable

Safety

All-steel frame with reinforced belt path
Aeroflex™ side impact protection system with EPP foam
Certified to FMVSS No. 213a and 213b standards
True tension™ door for secure installation in harness mode
Open belt path for easier booster-mode buckling
Push-on latch connectors for secure attachment
FAA certified for aircraft use in harness mode
No added fire-retardant chemicals

Comfort

Padded ergonomic armrests
All-weather micro knit fabric for year-round comfort
Leatherette-wrapped calf support for extended comfort

Premium details

Automotive-style leatherette accents
GREENGUARD Gold Certified for low chemical emissions
Durable materials designed for everyday use

Recommended use

Weight: 30–110 lbs
Height: 34–57 inches

Harness mode

Weight: 30–65 lbs
Height: 34–49 inches

Booster mode

Weight: 40–110 lbs
Height: 43–57 inches

Dimensions

Highest position: L 26.25 in x W 18.25 in x H 32.5 in
Lowest position: L 23.5 in x W 18.25 in x H 25.5 in

Weight

26.2 lbs

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