Crash tested, rear-facing design will catch your dog upon impact and act as a protective barrier to prevent contact with hard surfaces. For use with most dogs up to 35 lbs. Between sizes? Measure your dog using specs below as a guide. Five total seatbelt-grade plastic clips (reversible for use behind driver and passenger seats) lock PupSaver in place and integrate with seatbelt pretensioner in case of an accident to pull PupSaver safely over your dog. Full polyfill throughout (no hard plastic or foam pieces - easily fits in seats). Additional stitching, reinforced nylon backing at all attachment points. Heavy-duty metal j-hooks for lower LATCH (child safety seat) anchors in the back seat. New all-metal tether attachment system provides security at the base of the seat. Can be used in the front or back seat. Original PupSaver (all colors) - 24" (interior width - the part your dog sits on) / 28" (*exterior width at widest point - see note below) x 18" (seat bottom depth) x 16" (seat back height) *PLEASE NOTE: PupSaver Seats are COMPLETELY constructed of ballistic nylon. There are no hard foam pieces (like a booster seat), so the PupSaver is somewhat flexible. We very rarely encounter a vehicle that is incompatible. Seat Cover Fabric – Nylon Filling – Polyester Fiber Seat Pad Filling – Polyurethane foam Webbing – Polyester Tether Clasp/ Tether Attachment Points – Metal **EUC I only used this car seat for one road trip. My frenchie does not love being in the car!***