# Infant car seats with a belt tension indicator or lock\-off Which infant car seats include a belt tension indicator or a lock\-off to help tighten the vehicle seat belt? Maxi\-Cosi Peri™ 180° Rotating Infant Car Seat \- Kindred Collection: The base has a red\-to\-green tension indicator that shows when the vehicle belt is tight enough\. Chicco KeyFit Max ClearTex: The video demonstrates installing the base with either LATCH or the seatbelt but never both, adjusting the recline foot until the bubble is between the lines, connecting the lower anchors and pulling the strap tight, routing the seatbelt and using the lock\-off, and clicking the carrier into the base until it clicks; it advises reading the manuals or consulting a certified technician\. ### 1. [Maxi\-Cosi Peri™ 180° Rotating Infant Car Seat \- Kindred Collection](/products/ucp/maxicosi-com/7638087106614) (sold by maxicosi\.com) The base has a red\-to\-green tension indicator that shows when the vehicle belt is tight enough\. - Belt tightening aid: The base has a red\-to\-green tension indicator that shows when the vehicle belt is tight enough\. (guide) - Belt installation: Maxi\-Cosi provides an installation video and a downloadable user guide covering rear\-facing requirements, belt and LATCH base installation, headrest and harness height, rotation and recline, carrier and canopy use, accessory use and care instructions\. (guide) ### 2. [Chicco KeyFit Max ClearTex](/products/ucp/strolleria-com/8065093533770) (sold by strolleria\.com) The video demonstrates installing the base with either LATCH or the seatbelt but never both, adjusting the recline foot until the bubble is between the lines, connecting the lower anchors and pulling the strap tight, routing the seatbelt and using the lock\-off, and clicking the carrier into the base until it clicks; it advises reading the manuals or consulting a certified technician\. - Belt tightening aid: The video demonstrates installing the base with either LATCH or the seatbelt but never both, adjusting the recline foot until the bubble is between the lines, connecting the lower anchors and pulling the strap tight, routing the seatbelt and using the lock\-off, and clicking the carrier into the base until it clicks; it advises reading the manuals or consulting a certified technician\. (review) - Belt installation: The video demonstrates installing the base with either LATCH or the seatbelt but never both, adjusting the recline foot until the bubble is between the lines, connecting the lower anchors and pulling the strap tight, routing the seatbelt and using the lock\-off, and clicking the carrier into the base until it clicks; it advises reading the manuals or consulting a certified technician\. (review) 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 2026-11-02T18:47:10.801Z. 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)