G23859A - (Pkg 20) Aluminum Single Barrel Crimp Sleeve or Spacer 0.218" OD x 0.5" Tall
This is 0.218" OD (0.182" ID) x 0.5" tall aluminum spacer. It is strong and sturdy. We also had success using a hand-held crimper and squeezing it shut so it may be a single barrel crimp sleeve. Either way, this is a super deal on some versatile hardware! Sold in a package of 20.