We know a few things that Apple has included in the new MacBook Air lineup launched at WWDC yesterday– fourth-gen Intel Haswell chips, faster 802.11ac, 45% faster flash storage, dual microphones– but there could be a few other tweaks hiding inside that Apple didn’t announce live on stage. To get a better look inside, the folks over at iFixit have decided to give the 13-inch model its ritual teardown treatment.

Inside iFixit found a slightly larger battery, which on top of the new Haswell chip likely contributes to the increased, up to 12-hour battery life in the new MacBook Airs. The new model has a 7.6 V, 7150 mAh battery compared to the 7.3 V, 6700 mAh inside the previous generation.

Some other changes it found in the new MacBook Air:

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  • smaller SSD module
  • Updated AirPort card
  • No separate GPU
  • New heat sink clamp
  • Opposite-facing speaker cable connector
  • Samsung SSD
  • Samsung S4LN053X01-8030 (ARM) flash controller Eight 16 GB flash storage chips labeled Samsung K9LDGY8SIC-XCK0 Samsung K4P2G324ED-FGC2

iFixit gave the new machine a repairability score of 4 out of 10, noting issues such as proprietary screws, proprietary SSD & RAM, and lack of upgradeability:

As with the prior iterations, this MacBook Air’s biggest detractor is the lack of upgradeability. The RAM is still soldered to the logic board, and SSDs are not compatible between generations.