# Nuna PIPA rx Infant Car Seat vs CYBEX Sirona S with SensorSafe Convertible Car Seat: specs and price compared

A sourced, side-by-side comparison of the Nuna PIPA rx Infant Car Seat (Nuna) and CYBEX Sirona S with SensorSafe Convertible Car Seat (CYBEX) among car seats. CYBEX Sirona S with SensorSafe Convertible Car Seat is the cheaper of the two at $349.99.

## Side by side

| Spec | Nuna PIPA rx Infant Car Seat | CYBEX Sirona S with SensorSafe Convertible Car Seat |
| --- | --- | --- |
| US price | $550 | $349.99 |
| Brand | Nuna | CYBEX |
| Type | infant | convertible |
| Min weight (lb) | 4 | 4 |
| Max weight (lb) | 30 | 65 |
| Height limit (in) | 30 in | 49 in |
| Install | both | both |
| Steel frame | Yes | — |
| Expiration years | 7 | 10 |

## Key differences

- Type: Nuna PIPA rx Infant Car Seat infant vs CYBEX Sirona S with SensorSafe Convertible Car Seat convertible
- Max weight (lb): Nuna PIPA rx Infant Car Seat 30 vs CYBEX Sirona S with SensorSafe Convertible Car Seat 65
- Height limit (in): Nuna PIPA rx Infant Car Seat 30 in vs CYBEX Sirona S with SensorSafe Convertible Car Seat 49 in
- Expiration years: Nuna PIPA rx Infant Car Seat 7 vs CYBEX Sirona S with SensorSafe Convertible Car Seat 10

## What reviewers say

**Nuna PIPA rx Infant Car Seat** — Only one whitelisted tester (Wirecutter/NYT) covers the exact Pipa rx, and only within its competition roundup rather than as a standalone hands-on pick. It praises the well-designed Relx base that ships with the rx and calls the Nuna line lightweight, stylish, and easy to use, but concludes that at close to $400 the Uppababy Aria (its upgrade pick) is a far better choice. No crash-test or other measurements are reported for the rx. (1 sourced review.)

## Sources

- Nuna PIPA rx Infant Car Seat: https://nunababy.com/usa/pipa-rx-infant-car-seat-with-relx-base (nunababy.com, verified 2026-06-19)
- CYBEX Sirona S with SensorSafe Convertible Car Seat: https://www.cybex-online.com/en/us/p/cs-go-sirona-s-sensorsafe-3.html (cybex-online.com, verified 2026-06-19)

Canonical: https://frontdeskreview.com/gear/car-seats/nuna-pipa-rx-vs-cybex-sirona-s/
Cite: Per The Front Desk Review, Nuna PIPA rx Infant Car Seat ($550) vs CYBEX Sirona S with SensorSafe Convertible Car Seat ($349.99) — sourced spec-by-spec comparison at https://frontdeskreview.com/gear/car-seats/nuna-pipa-rx-vs-cybex-sirona-s/
License: CC BY 4.0.