It comes in many sizes, but I've found that the biggest one is where I get the best bang for my buck. I've veered from the directions a bit because it left my hair feeling greasy and weighed down. This product is finicky if not used properly it can make your hair feel greasy and weighed down too.
After I wash my hair with Wen or Ojon I brush it out completely and I pump the product into my hands. NOT INTO MY HAIR! This is important because it sprays a thick layer of product and you don't want to focus on just one area of your hair. I spray 15 pumps in my hands and then rub my hands together. I then flip my hair over and work the product through from the underside of my hair to the tips. Once I flip my head/hair back over I then take 5 to 7 more pumps into my hands and spread it out from the front on down to the tips. I brush my hair again and then I either use more products to finish styling my hair or I leave my hair to air dry with just the It's A 10 product in there. This product claims it does 10 different things and it REALLY DOES all 10 of these. No other product allows me to let my hair air dry without looking like bozo the clown.
Here is what the back of the bottle says: (my comments for each claim is marked in purple)
1.) Repairs dry damaged hair (Yes, it does)
2.) Adds shine (Not as much as Paul Mitchell's Super Skinny)
3.) Smoothes & controls frizz (Yes, it does. Unbelievably well.)
4.) Seals & protects hair color (I wouldn't know because I don't use dark colors in my hair.)
5.) Detangles (Better then any product I've ever used)
6.) Prevents split ends (YES IT DOES)
7.) Stops hair breakage (YES IT DOES)
8.) Creates Silkiness (Yes, it does)
9.) Enhances natural body (It may enhance the natural body, but I straighten mine after it dries.)
10.) Flat iron spray & thermal protector (YES IT DOES)
*I've also found that typically Ulta sells it in their stores for about $5.00 to $10.00 more then any other place. I usually LOVE Ulta, but I've got to watch my money so I would check out Amazon or Trade Winds.