Read the following paragraph and answer the question. Give ONLY the answer, no other words or explanation.

For example:

Answer: <most likely answer, as short as possible>.

Paragraph: It had stretched during whatever aerobics she does when removing these things and got stuck wrapped around her head and armpit . So now I am back to the breakaway collars , which I buy in bulk . I use the plastic coated paper tags for her information and replace as necessary . Now we are in a new home and the collar we moved here with has stayed on for almost 2 months !

Question: Why is she using a breakaway collar ?
The previous collar stretched and wrapped around her head and armpit which could be dangerous !
To prevent collar getting stuck.