iPhone Duo vs iPhone 18 Pro Max

117.8 mm163.4 mm84.1 mm78.0 mm

iPhone Duo: 117.8 × 84.1 × 11.3 mm · 254 g
iPhone 18 Pro Max: 163.4 × 78 × 8.75 mm · 249 g

Source: Apple technical specifications for iPhone Duo and iPhone 18 Pro Max. Body dimensions exclude the camera bump; foldable phones are shown folded.