Recasts, a type of implicit feedback, is widely used by EFL teachers for improving learners' communicative competence. Research suggests that teachers may use salience enhancement techniques in order to highlight the positive/negative evidence in recasts. This study was conducted to identify types of recasts and examine the relationship between recast features and learners' uptake and modified output. The data consist of 569 recast episodes retrieved from 15 NS teachers. The results revealed that recasts vary considerably in effectiveness according to factors such as the way in which they are provided. More specifically, short, segmented, and interrupting recasts were better predictors of modified output as they were more likely to help learners to notice the gap between the target form and its interlanguage form. The present study suggests that teachers equipped with such highlighting techniques would be able to promote learners' L2 development more effectively.