SKU: 27857835991
britax marathon convertible car seat onyx

britax marathon convertible car seat onyx Britax Poplar Convertible Car Seat (Cobalt Onyx)

$26.78 $29.76
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USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Aug 10 - Aug 15

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For Your Every Summer RSVP, with Code: SUMMER15

Description

britax marathon convertible car seat onyx Britax Poplar Convertible Car Seat (Cobalt Onyx)This item is an open box model and includes full manufacturer warranty. Purchase online for store pickup, we cannot ship these If you need to come in and test this model out as well as others in our showroom, be sure to book a consultation through our website. Ready to go with room to grow! The Britax Poplar Convertible Car Seat takes the stress out of moving to the next car seat stage thanks to the patented ClickTight Installation and slim SpaceSaver

This item is an open box model and includes full manufacturer warranty.

Purchase online for store pickup, we cannot ship these

If you need to come in and test this model out as well as others in our showroom, be sure to book a consultation through our website.

Ready to go with room to grow! The Britax Poplar Convertible Car Seat takes the stress out of moving to the next car seat stage thanks to the patented ClickTight® Installation and slim SpaceSaver™ design. This car seat accommodates up to 50 pounds rear facing to help keep your child riding safely even longer and easily switches to a forward facing car seat as your child grows. ClickTight Technology installation provides fully open seat belt paths that are clearly labeled and easy to access, and the automatic tensioner takes care of the tightening. Slim outside and spacious inside, the toddler car seat features 17" SpaceSaver technology designed to fit 3-across* without compromising on trusted Britax safety and premium comfort. The Britax car seat boasts a patented SafeCell® crumple zone and V-shaped top tether to help manage crash energy. The reinforced frame and belt paths provide strength and stability. Rear facing car seat cover fabrics are naturally flame retardant with no added FR chemicals and safe to machine wash and dry. *Britax cannot guarantee 3-across installation fitment in all vehicles

  • CONVERTIBLE DESIGN: Works as a rear facing car seat with the infant insert, rear facing and converts to a forward facing car seat
  • CLICKTIGHT INSTALLATION: With ClickTight, you know it’s right in just 3 easy steps: open, buckle and close 
  • INFANT INSERT: Specifically designed to fit newborns 22 lbs and under 
  • 5-POINT SAFETY HARNESS: Helps evenly distribute crash energy to keep your child safe
  • CONVENIENT BUCKLE: Fully open seat belt paths are clearly labeled and easy to access, while the automatic tensioner takes care of the tightening
  • PATENTED V-SHAPED TOP TETHER: Has 2 connection points to help slow and reduce forward movement in a crash; easily stores away when not in use
  • FLAME RETARDANT: The fabric is naturally flame retardant with no added FR chemicals
  • SAFECELL® TECHNOLOGY: Acts as a crumple zone, helping to keep crash energy away from your child 
  • ADJUSTABLE HARNESS: The 14-position harness and headrest move with one hand to grow with your child 
  • 5-POINT SAFETY HARNESS: Helps evenly distribute crash energy to keep your child safe
  • WASHER AND DRYER-FRIENDLY: No more hand washing or waiting for the cover to air-dry; just quick and easy cleanup, so you can keep moving
  • DISHWASHER-SAFE CUP HOLDERS: The 2 cup holders slide in-and-out for easy cleaning between rides
  • EASY-READ LEVEL INDICATORS: The 6-position and quick-adjust recline help you find the most comfortable fit for your child and the best fit for your vehicle

Specifications

  • Product Dimensions: 20.5"L x 17"W x 23.5"H
  • Harness Slot Heights: 8", 8.7", 9.4", 10.1", 10.8", 11.5", 12.2", 12.9", 13.6", 14.3", 15", 15.7", 16.4", 17"
  • Buckle Strap Depths: 4" - 7"
  • Child Weight: 5-65 lbs
  • Rear-facing Harnessed Height: Less than 49"
  • Forward-facing Harnessed Height: Less than 49"
  • Rear-facing Harnessed Weight: 5-50 lbs
  • Forward-facing Harnessed Weight: 30-65 lbs
  • Seat Area Depth/Width: 11" / 12"
  • Shoulder Width: 14"
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 27857835991

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4.7 ★★★★★
Based on 22 reviews
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Thomas W.
San Leandro, US
★★★★★ 5
⭐⭐⭐⭐⭐ Excellent Protection and Comfort — A Mattress Protector That Really Works!
Color: 3 Navy Blue, Size: Full
The BEDLORE Waterproof Mattress Protector, Full Size Mattress Pad with Deep Pocket (6″–15″) has been a fantastic upgrade to my bed setup. If you’re looking for reliable protection without sacrificing comfort, this protector delivers on every promise — and then some. 🛡️ True Waterproof Protection This mattress protector does exactly what it should — it protects. Whether it’s accidental spills, pet messes, or everyday body sweat, the waterproof barrier keeps everything from reaching your mattress. I’ve tested it with a few wet spills, and the liquid beads right up on the surface, giving me peace of mind that my mattress will stay fresh and clean for years. 🛏️ Soft and Comfortable Sleep Surface Unlike some protectors that feel stiff or noisy, the BEDLORE pad is soft, quiet, and comfortable. You barely notice it’s there, and it hasn’t changed the feel of my bed at all — it just adds protection while letting the mattress feel like my mattress. Sleeping on it feels smooth and cozy rather than plastic or crinkly. 📏 Deep Pockets Fit Perfectly The deep elastic pocket is one of my favorite features. It securely fits my mattress, which is on the thicker side, and stays in place even with nightly tossing and turning. The coverage from 6″ to 15″ means it fits almost any standard full mattress comfortably without slipping off or bunching up. 👍 Breathable & Quiet Despite being waterproof, this protector remains breathable, so I don’t wake up feeling too warm or restricted at night. It’s just the right balance — protecting without interfering with airflow or comfort. 💪 Easy to Care For Machine washing and drying are a breeze — it comes out clean and stays soft after every wash. I appreciate that it retains its shape and waterproof performance even after multiple washes. ✅ Final Thoughts Overall, the BEDLORE Waterproof Mattress Protector is a well‑made, comfortable, and highly effective mattress pad that offers great protection without the unwanted stiffness some other protectors have. It’s a smart way to preserve your mattress investment while still enjoying a comfortable night’s sleep. I’m very happy with it and would absolutely recommend it! ⭐⭐⭐⭐⭐
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 2, 2026
M
Verified Purchase
Mimi in Maine
Natrona Heights, US
★★★★★ 5
Excellent waterproof mattress cover find
Color: 5 Beige, Size: Queen
Good quality. Backing is waterproof with quiet material being such. Top cover is soft cotton which is hard to find. Followed proper washing & drying per tag instructions results were good. Em confident it will have longevity in quality. Also, a perfect regular queen mattress fit.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 6, 2026
L
Verified Purchase
Little Man's Mama
Pawtucket, US
★★★★★ 5
Fantastic mattress cover!
Color: 4 Black, Size: Twin XL, Color: 4 Black, Size: Twin XL
My son's bed needed a new mattress cover. The old one was a synthetic material that held stains, had snags and runs and didn't last long. So, I went hunting and found this one. I liked that it was quilted as well as waterproof, nice looking. I purchased one for my son's bed, black. Wow, these are really nice. They fit great and are so much more attractive, completely elevates the bed. They make a bit of noise when being put on the bed but are completely silent when laying on the bed. No more crinkle sound! I was so impressed I purchased one for my bed too! Never going back to the old covers. These will not disappoint.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 19, 2026
Z
Verified Purchase
Zach w
Dallas, US
★★★★★ 4
Great mattress cover
Color: 1 Gray, Size: California King
Fit our California king perfectly. Goes on just like a fitted sheet. Lightly padded and is infact water proof. Exactly what we were looking for and in our budget!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 25, 2026
S
Verified Purchase
StrongMcDorman
Draper, US
★★★★★ 5
Very nice Great Value
Color: 4 Black, Size: Queen
This Extremely nice stays on tight and I personally like the color instead of just white. Excellent vaule. I liked it so much I replaced all our old ones
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 16, 2026

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