The primary difference between these lifters is their maximum sheet size capacity. The 4.8M plasterboard lifter is designed to handle larger sheets, up to 4.8 meters in length (approximately 15.7 feet), while the 3.3M plasterboard lifter is suited for sheets up to 3.3 meters (approximately 10.8 feet) in length. Your choice depends on the size of the sheets you typically work with.