Apple’s new iPhone 6s and iPhone 6s Plus are on sale for the first time today, and the team over at iFixit have already given the smaller model its customary teardown — confirming a thicker, heavier display thanks to 3D Touch, and a smaller battery.

The iPhone 6s isn’t a whole lot different to its predecessor externally or internally, though there are some changes under the hood to accommodate new features. The biggest of those is the new pressure-sensitive 3D Touch display, which allows new gestures called Peek and Pop.

That display is the primary reason why iPhone 6s and iPhone 6s Plus are every so slightly thicker and noticeably heavier than their predecessors. The iPhone 6s’ display weighs 60 grams — 15 grams heavier than the iPhone 6’s display — which makes it as heavy as an iPhone 6 Plus display.

Another big change is the introduction of the Taptic Engine. Like that in Apple Watch and the trackpads built into the latest MacBooks, this provides users with haptic feedback when they use 3D Touch, and it replaces the traditional vibration motor for alerts.

The Taptic Engine sits right beneath the iPhone 6s’ battery, which explains why Apple had to make its lithium-ion cell slightly smaller this year. It has a 1,715mAh capacity, to be precise, whereas the iPhone 6’s battery has a 1,810mAh capacity.

The logic board inside the iPhone 6s boasts Apple’s new A9 processor, 2GB of LPDDR4 RAM manufactured by Samsung, a Qualcomm LTE modem, a 6-axis gyroscope from InvenSense, and a 3-axis accelerometer from Bosch Sensortec. The flash memory in this unit is from Toshiba.

Despite its proprietary pentalobe screws, the iPhone 6s isn’t too difficult to get into, and the display and battery are relatively easy to replace. As such, iFixit awards the iPhone 6s a repairability score of 7 out of 10.