Focus on Product Benefits
The biggest benefits the product offers should be made clear short and precisely.
Here it is important to always put the benefit to the front of the sentence and later backing it up with the characteristic(s) of the product.
The human brain makes quick selections as to what might be interesting or not, which is why the benefit should, for instance, be pointed out in 1-2 words at the start of the bullet.
Example for a dog house:
Always dry! This dog house will remain sound and dry at all times - thanks to highly modern and intelligent worksmanshit, as well as water neutralizing material x.
At the end of the day, products are bought to fulfill certain emotional needs. This can also be the case for seemingly trivial products, such as a mouse pad, which could lead to a more fun gaming experience, and indirectly even to more recognition among friends, for example.
This emotional benefit should always be pointed out strongly.
Always warm & clean! Get your cherished dog a warm and healthy home, supported by the newest technology in wind & cold protection.
Be Positive - Avoid Negations
Benefits or Characteristics should always be phrased in a positve manner.
In short this means that you should for the grand part avoid words such as "not", "without" or "no". People are able to grasp benefits a lot more easily when it is explained directly.
For example, a bottle should be described as "very easy to open", instead of "not difficult to open".
Limitation - 2 Rows Each
Theoretically 500 characters can be placed into a single bulletpoint, but due to reasons of readability it is not recommended to surpass 2 rows per bulletpoint.
Note: This is just the technical restriction. Amazon's style guides in your product category may indicate more limited numbers, which we generally advise to follow.
Pro Tip: Mobile devices will only display 3-4 bulletpoints. Similarly to the title the strongest arguments should therefore be placed in the first 3 bulletpoints.