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Britax Poplar S Narrow Convertible Car Seat

Regular price$399.99
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Britax Poplar S Narrow Convertible Car Seat
Britax Poplar S Narrow Convertible Car SeatOnyx

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The Britax Poplar S is a 17-inch-wide convertible car seat designed to preserve back-seat space while supporting extended rear-facing use. ClickTight installation opens the seat for direct access to the belt path, and the...

At a Glance

The Britax Poplar S is a 17-inch-wide convertible car seat designed to preserve back-seat space while supporting extended rear-facing use. ClickTight installation opens the seat for direct access to the belt path, and the included ReboundReduce stability bar adds rear-facing crash-motion management.

Width17 inches
Rear-facing5–50 lb
Forward-facing30–65 lb

Why Families Choose It

  • Slim outside, roomy inside: The 17-inch SpaceSaver shell is designed to support three-across planning in many vehicles, although Britax cannot guarantee fit in every vehicle.
  • ClickTight installation: Open the panel, route and buckle the vehicle belt, then close the seat to tension the installation.
  • Poplar S upgrade: The S model includes a ReboundReduce stability bar, removable head pad, and upper-body support pillow.
  • Fourteen-position fit: The headrest and no-rethread harness adjust together with one hand from 8 to 17 inches.
  • Wash-and-dry cover: SafeWash fabrics are machine washable and dryer safe and are made without added flame-retardant chemicals.

Specifications and What Is Included

Rear-facing fit 5–50 lb and 18–49 in
Forward-facing fit 30–65 lb and 35–49 in
Seat dimensions 20.5 D x 17 W x 23.5 H in
Seat weight 28 lb
Harness 14-position no-rethread harness and headrest
Safety structure Steel frame, SafeCell technology, V-shaped top tether, and two energy-management layers
Included Poplar S seat, ReboundReduce bar, infant inserts, and two cup holders/caps
Expiration / warranty 10-year expiration; 1-year manufacturer limited warranty

Is It Right for Your Family?

Best forFamilies needing a slim convertible seat, extended rear-facing capacity, and straightforward seat-belt installation.
Look elsewhere ifYou need a removable infant carrier or a booster mode beyond the forward-facing harness stage.

Important Use and Safety Notes

Actual vehicle and child fit can vary. Use the lower infant insert at or below 22 lb in rear-facing mode, follow the manual for insert and harness-pad rules, and use the top tether for every forward-facing installation.

Frequently Asked Questions

What is the difference between Poplar and Poplar S?
Poplar S adds the ReboundReduce stability bar, removable head pad, and upper-body support pillow.

Can it fit three across?
Its 17-inch width is designed for space-conscious layouts, but Britax does not guarantee three-across fit in every vehicle.

How long can it rear-face?
Up to 50 lb or 49 inches, whichever limit is reached first, subject to all manual fit rules.

Is it an all-in-one booster seat?
No. It is a rear- and forward-facing convertible harnessed seat.

Can the cover go in the dryer?
Yes. Britax SafeWash fabric is machine washable and dryer safe.

What do the color choices change?
They change the fabric fashion only; the core Poplar S structure and fit limits remain the same.

Britax Poplar S Narrow Convertible Car Seat $399.99 Free shipping • Easy returns

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