Eighths: For very heavy deadlifts, they have two ready-made loops for faster and safer use. You pass your wrist through one, place the bar in between, and then pass your wrist through the second loop as well.
with Hooks: With metal hooks for a more relaxed grip, they "hook" onto the bar, turning your hand into a pure "lever" without being limited by your grip strength. Ideal for recovery and injuries (e.g. tendinitis).