Quick answer

Choose the Back That Ass Up if you want intermittent suction plus vibration; choose the Shake That Ass if you prefer intense vibration with flexible positioning.

Suction vs. vibration: the core difference

The biggest difference between these two automatic masturbators is how they stimulate. Back That Ass Up uses Intermittent Suction Technology (IST) to create a powerful pulling sensation, while Shake That Ass relies on dual motors for 360° vibration. Your preference for suction or pure vibration will guide your choice.

Positioning and flexibility

Shake That Ass features a 360° design that lets you set it in any position—doggystyle, missionary, cowgirl—making it more versatile for different angles. Back That Ass Up is a fixed-position unit, so you'll need to hold it or mount it in a stable spot. If you like changing positions during use, Shake That Ass is the more flexible option.

Trade-offs at a glance

  • Back That Ass Up: suction + vibration: Two motors give you 6 suction levels and 12 vibration patterns. The intermittent suction adds a pulling sensation that pure vibrators don't offer. Best if you want variety in both suction and vibration.
  • Shake That Ass: dual vibration + 360° positioning: Two motors deliver strong vibration from all angles. The 360° design lets you set it in multiple positions without holding it steady. Best if you value positioning freedom and intense vibration over suction.
  • Price difference: Back That Ass Up is priced at USD 206.24 (was USD 274.99), while Shake That Ass costs USD 147.39 (was USD 219.99). Shake That Ass is the more budget-friendly option, but both offer strong features for their price.

Product facts at a glance

  • Back That Ass Up™: Back That Ass Up features Intermittent Suction Technology (IST) with 6 suction and 12 vibration modes powered by two motors. You get a unique suction-plus-vibration combo that many strokers lack, ideal if you want a sensation that mimics oral or pumping.

    Back That Ass Up™

    Back That Ass Up™

  • Shake That Ass™: Shake That Ass has dual powerful motors and a 360° design for flexible positioning in doggystyle, missionary, or cowgirl. The 360° design lets you adjust the angle freely, so you can find the most comfortable or exciting position without holding it in place.

    Shake That Ass™

    Shake That Ass™

Which one fits you?

Best for

  • Those who want a suction-and-vibration combo for a more varied experience
  • Users who prefer intense vibration and flexible positioning without needing to hold the device

Not for

  • If you dislike suction sensations, skip Back That Ass Up
  • If you need a fixed-angle stroker, Shake That Ass may feel too loose