Square unveiled a new version of its popular credit card reader that shaves some bulk from the device and improves performance. The sleeker reader has the same external look as its predecessor, but trims its width by 45 percent and boosts its accuracy with new internal components designed by Square itself.

The inspiration for this new design comes in part from Jesse Dorogusker, the VP of hardware at Square and former head of accessories at Apple. Dorogusker took skill in making small things even smaller and applied them to the new Square Reader in a design process that he explained to Wired.

Dorogusker and his team spent a lot of time improving the card reading device, not just making it smaller and lighter. The way the device handles swiping has been overhauled, making it both more accurate and easier for the user.

In the old Reader, Square used a standard read head, more or less the same one that’s been in every credit card reader and tape deck since 1985. Those worked well enough, but they were far from optimal. First, they weren’t doing all they could to ensure successful swipes. The magnetic stripe on your credit card stores data in two separate bands. The old Reader grabbed from just one. With their new custom read head, Square can grab both, which makes every swipe more accurate, and more likely to work on one try.

The redesign also gave Dorogusker and company a chance to tweak the feel of the swipe itself, which is a crucial detail that makes the product itself feel trustworthy despite its tininess. By tweaking the design of the spring to which the magnetic read head was attached, the team was able to fine-tune the friction customers feel when swiping their card.

Square even tweaked the manufacturing process to produce a better magnetic reader and designed a custom chip that was the key to the improving performance and reducing the size of the device.

“On one level, developing a custom chip gave Square total control over the processes at the heart of the product: Decoding the magnetic signal from the credit card, encoding the electrical signal being sent to the smartphone, and all the encryption that happens in between.”

“In terms of the design of the internals, though, the chip offered another fantastic advantage: an opportunity to ditch the Reader’s battery … As a result, the new Reader dropped the battery and two millimeters along with it.”

You can read more about the new design in the Wired article and check out the Reader itself on Square’s website. The Reader is free, while transactions are charged at a rate of 2.75%. It is compatible with iOS and Android devices.