# Convertible car seats and vehicle headrest fit Which convertible car seats fit well with a vehicle's headrest? Britax Poplar ClickTight Convertible Car Seat: Shows the updated ClickTight system: push two buttons on the side, lift the panel, thread the seat belt through, push down to lock\. Also shows 14\-level headrest adjustment and non\-rethread harness; infant insert used up to 22 lbs rear\-facing; recline mechanism at the bottom\. Seat is 17 inches wide without cupholders and 20 inches with them\. Britax Poplar S ClickTight Convertible Car Seat: The Poplar and Poplar S are described as among the skinniest car seats on the market, at 17 inches wide externally\. The checked facts describe each seat's own headrest adjustment and width, not how either seat fits against a vehicle's headrest, so no fact confirms vehicle headrest fit\. ### 1. [Britax Poplar ClickTight Convertible Car Seat](/products/ucp/albeebaby-com/9564473721063) (sold by albeebaby\.com) Shows the updated ClickTight system: push two buttons on the side, lift the panel, thread the seat belt through, push down to lock\. Also shows 14\-level headrest adjustment and non\-rethread harness; infant insert used up to 22 lbs rear\-facing; recline mechanism at the bottom\. - Headrest: Shows the updated ClickTight system: push two buttons on the side, lift the panel, thread the seat belt through, push down to lock\. Also shows 14\-level headrest adjustment and non\-rethread harness; infant insert used up to 22 lbs rear\-facing; recline mechanism at the bottom\. (review) - Width: Seat is 17 inches wide without cupholders and 20 inches with them\. (review) - Installation: ClickTight install: open, thread & buckle, click closed\. (guide) ### 2. [Britax Poplar S ClickTight Convertible Car Seat](/products/ucp/albeebaby-com/9564453077223) (sold by albeebaby\.com) The Poplar and Poplar S are described as among the skinniest car seats on the market, at 17 inches wide externally\. - Headrest: - - Width: The Poplar and Poplar S are described as among the skinniest car seats on the market, at 17 inches wide externally\. (blog) - Installation: - Every value in the table is a fact RoboTrunk checked, linked to the page it came from\. A dash means no checked fact fills that cell\. Prices and stock change, so this page prints neither: each product name links to its RoboTrunk page, which shows them live\. Written 2026-10-10T02:10:21.393Z. This page is published by RoboTrunk, a store built for shopping agents. The store named on this page sells the product and ships it. RoboTrunk is not the seller and never holds the money. Buying works in one path. RoboTrunk's tools prepare a checkout at that store, then hand back a short-lived link. The person approves the total; once RoboTrunk has checked the store's total against it, the person is given the checkout link to tap in their own browser, or, if the person prefers and gives permission, their agent may open the link and finish there, and payment always happens on the store's own checkout page. RoboTrunk never takes the payment or sees a card. Where the rest of this site is: - /agent/story.md is what RoboTrunk is and how it works, in full. - /agent/tools.json is every tool, its arguments and its answers. - /agent/merchants is every store you can buy from through RoboTrunk. - /products/ucp is every store's indexed products. - /products/search is one search across every store, in plain words. - [What RoboTrunk is](/agent/story.md) - [Every tool, in your browser through WebMCP](/agent) - [The tools and how to call them](/agent/tools.json) - [The stores you can buy from](/agent/merchants) - [Every store's products](/products/ucp) - [Search every store at once](/products/search)