Nuna PIPA Base vs. PIPA RELX Base Comparison

Nuna PIPA Base vs. PIPA RELX Base Comparison

In addition to numerous infant car seat models, Nuna now offers two choices of car seat bases, too!

New for April 2020, the PIPA RELX base builds on parent-favorite features already seen in the PIPA base. The base can be purchased separately for any Nuna infant car seat and is included with purchase of the new PIPA RX and PIPA Lite R models.

With its added adjustability and recline options, the PIPA RELX base helps parents feel confident that their child's car seat is securely installed and adds comfort for your baby, too. But the original Nuna PIPA base included with the PIPA, PIPA Lite and PIPA Lite LX car seats has long been a best-seller, with safety features that go above and beyond industry standards.

Parents can now choose between five Nuna infant car seats (see this PIPA Series comparison for an overview) and either the PIPA or PIPA RELX base when buying an extra for a second vehicle.

With two excellent base options that appear similar, you may be wondering which base will best suit your needs. No need to stress, you can relax—because we have put together a comprehensive comparison in this article!

Nuna PIPA Base vs. PIPA RELX Base Safety Features

As the foundation for the safety of your infant car seat, both the PIPA and PIPA RELX bases include leading safety features, like a load leg and rigid LATCH system.

But the PIPA RELX adds several features—like a more adjustable load leg, multi-position LATCH connectors, an anti-rebound panel, and a redesigned seatbelt lockoff—that can make the base easier to install in a wider range of vehicles and seating positions. See the RELX base in the video below.

Both bases include a steel stability leg, also called a load leg, which extends from the front of the base down to the floor of your vehicle. The purpose of this leg is to help reduce rebound motion by minimizing forward rotation of the car seat in event of a collision.

Nuna's research suggests the load leg minimizes forward motion by up to 90 percent, while Consumer Reports says that a load leg can reduce head injury risk by 46 percent.

Consumer Reports also noted that the load leg performed best in testing when used in conjunction with the lower anchors for installation, called the LATCH system. We'll explore the rigid (steel) LATCH connectors on both Nuna bases in the next section.

On the PIPA base, the load leg consists of two sections that can adjust to almost 12 positions and accommodate a variety of vehicle types, including center position seating in some vehicles. The leg has a grey button in front that allows you to shorten it, but the leg does not lock into shorter positions and will continue to extend. A red-to-green indicator on the front of the leg lets you know when it is safely in contact with the vehicle floor.

The load leg on the RELX base has three sections with 17 positions to allow for greater flexibility, especially when installing the base in vehicles with a hump in the center seat.

Additionally, Nuna moved the red-to-green indicators to the sides of the RELX load leg so they're easier to see. The PIPA indicators are on the front of the leg and can be more difficult to check.

Nuna PIPA Base vs. RELX Base

Nuna PIPA Base vs. PIPA RELX Base Installation

Known for its 5-second installation and green-for-go safety indicators, the PIPA base has always had a hassle-free install.

With the PIPA RELX, Nuna is making the install even easier by updating each component of the base: the load leg, rigid LATCH connectors, seat belt lock-off, and recline and leveling adjustment.

Another unique part of the RELX design is its new anti-rebound panel at the back of the base. The anti-rebound panel inhibits movement and helps ensure the the base is snug against the vehicle seat.

You can install your PIPA or RELX base in two ways: with the rigid LATCH connectors that click into your vehicle's lower anchors or with the vehicle seatbelt itself through the provided belt paths.

Seatbelt installation is ideal for older vehicles and center seats that don't have lower anchors for you to use, but the LATCH installation may be faster.

Nuna PIPA Base vs. PIPA RELX Base


On the PIPA, the rigid LATCH connectors have one position, so in some vehicles, there may be space between the base and the vehicle seatback.

The redesigned connectors on the PIPA RELX base help you get a tighter install, thanks to four settings on the connectors that ratchet tighter as you push the base into place towards the back of the seat. This will help minimize movement of the base once installed, solving a potential challenge seen in some vehicles with the PIPA base.

See the four LATCH connector positions on the RELX base in the image below.

LATCH Connector Positions on the PIPA Base


You can use the vehicle seatbelt to install either the PIPA or PIPA RELX base.

The PIPA base uses two belt guides and a blue lock-off mechanism to secure the seatbelt in place, with the shoulder belt and lap belt locked together into the base. This is quick and easy to use, but in some vehicles it could pose a challenge depending on the thickness of the seatbelts, which could make it more difficult to lock.

The PIPA RELX base uses a new lock-off mechanism that separates the shoulder belt and lap belt into different locations to prevent bunching, creating a seamless path for you to thread the belt. Simply lock both into place with a one-piece lock-off panel.

Mother Loading A Nuna PIPA RELX Base into Her Vehicle


The PIPA RELX base has four recline positions to ensure the car seat is installed at an angle that's safe for your baby, while the PIPA base has only a recline foot.

When leveling the PIPA base, you will use the built-in bubble indicators on either side of the base to make sure baby's seat is safely reclined. If needed, the back of the base can be raised using a recline adjustment foot. Although easy to use, the recline foot may affect the seat fabrics in some vehicles. Additionally, the PIPA base must be leveled with the recline foot before installation.

To level the PIPA RELX base, you don't need to study levels or lines. Simply install your car seat using the LATCH connectors or seatbelt lock off, then press the blue buttons on the sides of the seat to adjust the recline to the setting recommended for your baby's weight.

Positions 1 and 2 are more reclined for babies from 4-20 pounds, and positions 3 and 4 allow your baby to sit more upright after reaching 21-32 pounds. You can even adjust the seat recline with the infant car seat attached to help soothe a fussy baby.

In addition to being easier to use and adjust, the design of the RELX recline mechanisms also allows the underside of the base to be more smooth to further protect your vehicle's seat fabrics.

Nuna RELX Base Recline Controls

Nuna PIPA Base vs. PIPA RELX Base Specifications

The PIPA RELX base is larger and heavier than its counterpart because of the new anti-rebound panel, adjustable rigid LATCH, redesigned load leg, and built-in recline mechanism. Here are the weights and dimensions for each base.


  • Weight: 14 pounds
  • Dimensions: 8.3" H x 22.8" L x 12.2" W

    PIPA RELX Base

    • Weight: 18.6 pounds
    • Dimensions: 12" H x 23.75" L x 13" W

      If you will not often be traveling with the base itself, the RELX base will be the most full-featured and will be even more convenient to install. However, if you travel often and need to bring the base with you—or if you will often transfer the base between vehicles—the lighter PIPA base may be a good choice.

      Most of the time, the bases will primarily stay in your vehicle, so the lighter and more portable infant car seat (whichever PIPA you choose!) can be clicked in and out of your car with ease.

      Nuna PIPA Base vs. PIPA RELX Base

      Nuna PIPA Base vs. PIPA RELX Base Price

      Compared with the PIPA base, the PIPA RELX base adds $40 to the cost because of the additional customizations built into its design.

      Car Seats Compatible with PIPA Base and PIPA RELX Base

      All Nuna infant car seats fit all Nuna car seat bases, no matter the model or year of manufacturing.

      The RELX base is compatible with all versions of the Nuna PIPA infant car seat series, including the PIPA, PIPA RX, PIPA Lite, PIPA Lite R, and PIPA Lite LX.

      Nuna PIPA Series

      If you already have a Nuna car seat and want to take advantage of the new PIPA RELX base features, it will work with your car seat! However, only the new PIPA RX and PIPA Lite R will come with the PIPA RELX base automatically.

      The Nuna PIPA, PIPA Lite, and PIPA Lite LX will continue to include the PIPA Base with purchase as before, and Nuna will be offering the PIPA and RELX bases simultaneously.


      Strolleria is a family-owned and operated retailer dedicated to making the baby gear buying experience less overwhelming for parents. If you have more questions about the PIPA vs. PIPA RELX infant car seat bases, feel free to contact us by starting a live chat, calling 480-442-9433 or e-mailing