The Boost Air Protect Belt-Positioning Booster Car Seat by Safety 1st offers advanced Air Protect® protection, all the way up to 100 pounds when used with the back. The Safety 1st Boost Air Protect Booster Car Seat Features: Air Protect Advanced Side Impact Protection Belt-positioning booster from 30-100 pounds Adjustable head rest Slide-out cup holder on either side Converts to a backless booster