Tiger Woods’ driver was among those tested by the R&A on Monday at Royal Portrush.

According to a Golf.com report, Woods handed his TaylorMade M5 driver to manager Rob McNamara after playing in a practice round with Dustin Johnson and Rickie Fowler on Monday. McNamara then brought the club to the driving range, where the testing was being done.

Last year at The Open, the R&A tested 30 drivers at random to make sure the clubs were conforming, measuring the characteristic time of each clubface, which, as Golf.com notes, is the amount of “rebound effect” the face produces. None of the drivers tested at Carnoustie were in violation.

The R&A confirmed to Golf.com that a “similar number” of tests are being conducted this year.