This butterfly came from Celtic Tatting Knots & Patterns by Rozella Linden. The thread is size 10.
I've done 3 patterns from her book and this one I found to be the easiest.
And I would like to suggest for the next printing of this book, if the samples for the step by step photos all be in the same color it would cut down on the confusion and fustration I had while working on the flower. Changing colors half way through may look pretty on the page but if you're comparing one photo to the other, it's very confusing. I'm off my soap box now, thanks for listening.