The Nuna PIPA RELX Extra Base is one of the most thoughtfully engineered infant car seat bases on the market, built around an adjustable stability leg that fits center seating positions and a wider range of vehicles than most bases can accommodate — a genuine breakthrough for families who need flexibility without compromise.
True Lock Installation, Refined
The RELX base installs in 5 seconds via Nuna’s True Lock system, with a steel-reinforced rigid latch that adjusts across four positions to eliminate the gap between the base and your vehicle seat. Colored indicators on both the rigid latch and stability leg turn green when each connection is properly secured, removing any guesswork from the process. Our CPST-certified staff installs and inspects bases daily in our Portland showroom — and every Nuna purchase at Posh Baby includes a complimentary car seat safety installation and safety check by our trained staff.
Engineered for Every Stage & Every Vehicle
The bubble-free, numbered recline guides allow you to adjust the riding angle as your baby grows without uninstalling the base — four positions, all accessible on the go. The locking three-piece steel stability leg adjusts across a wide range to fit most vehicles including middle seats, while a crumple zone within the leg absorbs impact and minimizes force transferred to baby. The lockoff with easy-access belt path makes seat belt installation equally straightforward.
Compatibility
Compatible with any Nuna PIPA series infant car seat. The low-profile base and smooth platform protect your vehicle’s upholstery while making loading and unloading the infant seat easier.
Shop Nuna Pipa Series & all car seat accessories.
Posh Baby is a family-owned Portland boutique specializing in premium baby gear since 2006. Enjoy Tax-Free shopping in most states.
Build Your Baby Registry at Posh Baby
Create your universal baby registry with Posh Baby Portland — and add items from any store in the world. Our expert registry concierge team is here to guide you through every product category, from strollers and car seats to nursery furniture and essentials. Enjoy exclusive registry rewards, tax-free savings in most states, and the confidence of buying from a family-owned boutique that truly knows baby gear.
Universal Baby Registry
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Boutique Services Offered
Free Car Seat Install
Education Driven Experience
Try Before You Buy
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Registry Rewards
Purchase any 3 of the items below — whether you buy them yourself or your guests do — and receive a 5% rebate gift card based on the total of those 3 items. Use it in-store or online.
Mattress Nursing Chair Bassinet Car Seat Stroller Carrier Bouncer
Eligible items must be purchased from Posh Baby. Gift card is issued after qualifying purchases are confirmed.
