Depending on your set up, the bag’s springs either feel like they move too fast or two slow, and personally I’d have loved to see a mid-point. As this swings so fast it does work out quite nicely for real fast drills where you’re just lightly hitting the bag. The second method of training with the Everlast Hyperflex is by locking the bottom spring so that only the top spring moves.

The high-tension spring in the cobra bag allows you to practice your defensive footwork and head movement at rapid speeds, even without a partner.

Moving on from visuals, when we start to look at the materials it’s clear again that Everlast have tried to put together a really nice product.

Hyperflex (Unlock Base, Unlock Neck) setting is ideal for ultimate accuracy, speed, and agility training, and simulates sparring sessions for striking and defense. I find using the bag like this really challenges your accuracy, because the bag itself doesn’t always travel at a consistent speed. The 8-inch target ball is filled with infused foam, providing ideal resistance without the need for bladders or an air pump. For that reason, I tend to use it as a kind of "break" during longer bagwork sessions, or something similar.This spring means that when you punch, it will momentarily swing away, before swinging back towards you. It has a fully adjustable industrial steel tubular construction that is suitable for professional and home training. This added randomness does mean that I find this really satisfying for practising footwork and evasion. So far seems pretty sturdy, I am worried about the plastic joint that connects the spring and rod to the frame but so far it's holding up. If you were to measure and transfer it with jugs or similar, you’d be there for a ridiculous amount of time.