Britax Frontier Clicktight Combination Harness-2-Booster Car Seat, Vibe

Toddler to Big Kid: Easily transition from harness to belt-positioning booster as your child grows
Easy installation: Patented ClickTight makes car seat installation as simple as buckling a seat belt
No rethreading, ever: Quick-adjust 9-position harness with headrest for a comfortable, secure fit
Surrounded in safety: 2 layers of side impact protection, steel frame, impact absorbing base, and forward-movement reducing v-shaped tether
Relax & Recline: Multiple recline positions ensure comfort and the best vehicle installation angle
Removable Cup Holders: Keep drinks and snacks close at hand
Fits: Forward-facing harness mode 25-90 pounds, Booster mode 40-120 pounds; Maximum Dimensions: 19 W x 36 H x 21 D inches