I got it right from Tilt. I wanted to pick a color and Amazon only had black.
I seem to really have a hard time with the spund window so this should help, i imagine, with out the need for multiple samples.
Aside from actually being present when you need to be... I'm finding that the spund window is not that tricky. I have probably sent beer to the keg to spund with MORE gravity left than there should have been and while those beers may have been slightly more lively, they were great. I had a 5% blonde ale fermenting since last Friday night and on Monday night the activity was getting very slow. I thought "no way it's done in three days. No way." I checked the gravity on Tuesday morning and it showed 1.010. So I quickly sent it to the keg and it may or may not naturally carb. If not, I'll hit it with CO2. The TILT would have helped for sure.
Also: I'm not using the spunding valve anymore either. I just send it to the keg with a closed-transfer and let the rest happen. The valve doesn't seem necessary.