they r very light. you cant feel them on you at all. they dont slide off or to the side. they r not expensive i think i got mine for 25 dollars. they look tight. they help protect you crawling i guess i dont know i dont crawl. they help you when you dive thats for sure . they come in many different sizes.
Weaknesses:
in the summer its just another thing to get you hot
Conclusion:
its worth the price.
i would recomend it to someone.