The Finis Foam Pull Buoy is a classic tool for developing your swimming technique. Placed between your legs as high as they will go, Pull Buoys were traditionally thought of as a strength development tool since the buoyancy allows you to turn off your leg kick and so the upper body can be isolated.
These days we use pull buoys for slightly different stroke technique reasons. Whilst you have to be careful not to become reliant on them, they are an extremely valuable tool which every swimmer should have in their kit bag.
How And Why To Use A Pull Buoy
Required for many Swim Smooth drills such as sculling and doggy paddle, a pull buoy gives your legs additional lift so you don't have to kick and can simply focus on your catch and pull: