Thanks! Yep, 1/8".
BTW, sleeving is for those who have plenty of time on their hands, and willing to void the PSU warranty, as a good sleeve job requires popping the PSU cover and pulling the sleeving through it's wire bundle hole (here is a good place for zip ties, but the pros will heat shrink it too). Originally did mine on an Antec years ago, and then another Antec, but stopped at the SATA connectors (got tired of 1001 hand cuts again), as then (and probably still today) you had to snip them off, and reattach them after sleeving (the connectors are too wide to get a snug PET sleeve look).
The results are beautiful though. Highly recommend using black, since over time the dirt will show on the UV pet sleeving (used UV Orange in my case).