Exactly as described and delivered quickly. Packed like in a dump truck to Mars - well protected! At first it didn't seem like the isolator would fit on my CK17 burner, but it snaps into place when urine is pushed out. The insulator ID is approximately .050" smaller than the standard CK insulator, but it has a lip that snaps over the CK head. Just long enough that I can hold the burner's body like a pencil and run my hand over the last two fingers. The gas lens allowed me to maintain the same/better shielding with about half the gas flow.