What is the Native Ad CTA max character count/length

[br_android_dev]

I’ve looked at the Native Ads Best Practices and didn’t see a max character count returned from the CTA text type. I do see title as 25 max and text as 100 max but no listing for CTA. I have seen one ad come back with the following 17 character string:
Take Fit Test Now
I need to know this so I can handle long CTA strings accordingly in my UI and set the text size appropriately to fit a long CTA string.

[ekinbenho]

Hey br_android_dev,

There is no max limit for CTA text for publisher direct serve creatives. For DSPs, CTA text is optional and defaults to ‘Install’ if nothing is passed. A 15 character limit is recommended for our DSPs, but there is no limit.

https://dev.twitter.com/mopub-demand/ad-formats/native-best-practices