Though Apple hasn’t released its own numbers regarding Apple Watch sales, research firm Slice Intelligence estimates that the company sold 2.79 million watches as of mid-June. And with the cheapest Apple Watch costing $349, about 17 percent of shoppers nevertheless forked out for more than one band, at a minimum of $49 each. The data was given to Reuters by Slice, based on email receipts of over 2 million online shoppers.

The $49 band is the sport, and the black version is the most popular choice overall. Research firm IHS estimates that the band costs $2.05 to make, not including packaging and shipping, making the accessories a very profitable venture for Apple.

“Of course, because it’s Apple, it’s sell the razor, sell the blade,” said IHS analyst Kevin Keller.

Earlier this month, Apple announced that it has almost caught up with backlog orders for the Apple Watch, meaning that some models will be available to purchase in-store in 16 countries from June 26. It is already available in multiple countries including the U.S., Canada and Australia.