Cool Lipo is an ideal choice for under the chin.  Depending on your age and the laxity of the skin in the area, you should have a very satisfactory result using the services of a competent surgeon who performs this procedure on a regular basis.

If there is a lot of skin laxity of  the area already,  the "tightening"  you seek may not be significant enough for a pleasing result.  It is possible you would need a neck lifting procedure as well to achieve optimum results.  This, of course, can only be assessed in person.

I use the Cool Lipo Device in almost all my liposuction cases, including tummy tucks!  I find that the skin tightening benefit is evident in even larger areas compared with liposuction without the Cool Lipo laser device.

Of course, as always, adhering to post-operative instructions is very important.  With liposuction under the chin, it is important to wear the head strap provided to you by the surgeon for as long as is recommended.