Kingz, I use one of these: 306 to 510 Drip Tip Adapter - Avid Vaper
The base of the UFS comes right up to the bottom of that adapter sleeve, so juice control gets properly closed when I need to. The adapter is a good tight fit, too, so it won't get popped off unless you really tightly crank the JC closed. Since the top of that adapter is a little wider than a 510 atty tube, though, I have to either use a thinner o-ring in the top cap for short mode (the o-ring that comes with the new version atty extender works well for this) or use an atty extender for full mode. Works like a charm, though
The base of the UFS comes right up to the bottom of that adapter sleeve, so juice control gets properly closed when I need to. The adapter is a good tight fit, too, so it won't get popped off unless you really tightly crank the JC closed. Since the top of that adapter is a little wider than a 510 atty tube, though, I have to either use a thinner o-ring in the top cap for short mode (the o-ring that comes with the new version atty extender works well for this) or use an atty extender for full mode. Works like a charm, though
