PreCheck reduces the intensity of the actual screening: walk-through metal detector instead of millimeter wave scanners, can leave your shoes on, keep liquids/laptops/etc in bags, and at airports with a mix of 2D X-ray and 3D CT scanners for baggage, the PreCheck lanes are more likely to have the older X-ray scanners.
The reduced scrutiny is the justification for the fingerprinting appointment background check. I haven't seen anything similar in Europe, but busy airports are far more likely to have an efficient security setup that can already cope with leaving liquids in bags and the like. Many US airports still have security checkpoints that look like temporary installations, with portable equipment--even when they're brand new redevelopments!
Usually, the queues are shorter for the PreCheck lanes, but this isn't guaranteed.
CLEAR replaces having an an agent compare your face to your ID with having a kiosk compare your biometrics. The real advantage comes from having a CLEAR employee then walk you past the queue to get by the normal ID checking podium.
You need both to get the guaranteed short queue and the less intense screening.
(And then there are the programs to expedite the immigration/customs process too, but at least those include PreCheck, so you don't need all three...)
The reduced scrutiny is the justification for the fingerprinting appointment background check. I haven't seen anything similar in Europe, but busy airports are far more likely to have an efficient security setup that can already cope with leaving liquids in bags and the like. Many US airports still have security checkpoints that look like temporary installations, with portable equipment--even when they're brand new redevelopments!
Usually, the queues are shorter for the PreCheck lanes, but this isn't guaranteed.
CLEAR replaces having an an agent compare your face to your ID with having a kiosk compare your biometrics. The real advantage comes from having a CLEAR employee then walk you past the queue to get by the normal ID checking podium.
You need both to get the guaranteed short queue and the less intense screening.
(And then there are the programs to expedite the immigration/customs process too, but at least those include PreCheck, so you don't need all three...)