The Nuna Aace Booster Seat in Lake is the last booster seat your child will ever need — growing from high back booster through no-back booster mode with a 3D Growth™ system designed to adapt at every stage. From cute preschooler to independent pre-teen, every element from fabric to foam is smartly sourced to be flame resistant with no added fire retardant chemicals.
3D Growth™ — Engineered to Grow With Your Child
The 3D Growth™ system works in three dimensions simultaneously. A one-hand 9-position height-adjustable headrest grows up with your child, while the shoulder system expands outward in sync with every headrest adjustment. Three seat depths give growing legs plenty of support and space at every stage — no manual reconfiguration required.
Security & Side Impact Protection
Energy-absorbing foam and SIP pods deliver advanced side impact protection, while a belt positioner aids correct shoulder belt routing and minimizes user error. Colored belt path indicators further reduce installation risk, and lower anchor connectors secure the seat to the vehicle during use or transport — adding an extra layer of confidence at every buckle-in.
Comfort From Preschool to Pre-Teen
Eight recline positions in high back mode keep every ride comfortable as your child grows, while ventilation panels within the shell maintain a comfortable climate year-round. Breathable, machine-washable knit fabric and built-in armrests round out a seat designed for the long haul. The sleek micro-knit fabric removes easily for machine washing, and a removable, dishwasher-safe cup holder keeps drinks within reach.
2-in-1 Design & What’s Included
The Aace converts from high back booster to no-back booster as your child grows — high back mode fits 40–110 lbs, 38–60", ages 4+; no-back mode fits 50–120 lbs, 38–60", ages 5+. Dimensions: 22.5"H × 12"W × 14.5"L; weight 15.6 lbs. Every Aace includes the starter kit: cup holder, belt-positioning clip, and set of LATCH guides.
Car Seat Installation at Posh Baby
Every Aace purchased at Posh Baby includes a complimentary car seat safety installation and safety check by our trained staff — because confidence at installation is just as important as the seat itself.
Pair your Aace with a compatible Nuna stroller or browse our full range of car seat accessories at Posh Baby.
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
When you register with Posh Baby, you can add gifts from our store, Etsy, Amazon, Target, or that little boutique you love — shop small, shop anywhere. Add items regardless of whether your favorite stores even have a website. Our easy-to-manage registry has no limits on what you can add.
One registry. Every store. Endless possibilities.
Boutique Services Offered
Free Car Seat Install
Education Driven Experience
Try Before You Buy
Free Stroller Assembly
Shop tax-free in most states** **exceptions may apply
Loyalty Rewards
1 Point for Every $1 Spent
Earn loyalty points for purchases and other actions, then turn those points into real rewards. We believe in rewarding the families who choose to support us — we don't take your trust for granted.
Thank you for shopping small.
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.
