If you are considering a Special Ops profession, particularly one that could involve waterborne operations, you will need to learn the modified sidestroke, also called the combat swimmer stroke. The uniqueness of this stroke is that it can be used either with fins or without. This modified sidestroke has been unofficially nick named “the CSS” and is used
Pool training for open water swimming – HUUB Design
Combat Sidestroke Common Mistake #8: Improper Hand Recovery – by Streamlined Performance
Combat swimmer stroke (CSS) vs Elementary Side Stroke. Both are great for the Navy PST.
Special Boat Service - Wikipedia
SEAL SWCC COMBAT SIDESTROKE GUIDE
Timing Issues With The Combat Swimmer Stroke /Side Stroke
SEAL SWCC COMBAT SIDESTROKE GUIDE
Combat Sidestroke: Common Mistakes – Breathing On 2nd Pull
Want to Be Special Ops? Learn the Combat Swimmer Stroke - Breaking Muscle
To Pullout or Not: CSS Debate – Stew Smith Fitness
Navy SEAL Workout: Train Like the Best
How Non-Swimmers Can Get Ready for BUD/S or Aquatic Special Ops
Combat Side Stroke Booklet (DIGITAL DOWNLOAD) – Streamlined Performance