After buying this trimmer and making it half way through the included trimmer string I found a problem that makes this trimmer a Do Not Buy. The trimmer I received was in fact not the trimmer pictured in the product description. It turns out that the same model has four different configurations. DeWalt calls them Types 1, 2, 3, & 4. The trimmer pictured is a Type 1,2,or 3. I received a Type 4. This is very important because the Type 4 DCST920B has a different string head on it and this is where the problem is. The string head / spool on the Type 4 does not have a divider for each side of the string as most all trimmer spools do. Both strings are found together on a non divided spool making it prone to snags. In the evolution of power trimmers, they found out a long time ago that dividing the spool prevents snags and problems.
So back to the original story. I got half way through the provided line and it appeared to be out of string. I opened up the head and there was plenty of string left. I rewound all the string methodically and started to work again. Two minutes later it failed again. One more time and it was time to take DeWalt up on their 90 day guarantee. This is the 4th power trimmer I've ever owned and I'm clearly done messing with 2 stroke engines. I really wanted a trimmer that just worked. After the trouble with the string breaking, I went back to the Amazon ad and noticed that the trimmer shown had the different head assembly. Further research showed that all the video reviews I had looked at before buying had this better type of head with separate sides for the string.
I have included a photo and parts break down so that you can see exactly what I mean about this particular trimmer head and spool and how it differs from the one in the ad. I hope seeing the pics and knowing the story helps you out.