With the unlocked phone revolution possibly soon upon us (once again), Apple has begun selling an unlocked, SIM-free iPhone 5sfor the full price - meaning that the iPhone 5s can be had on carriers contract free. But there's a hitch.

Apple's unlocked, SIM card-free iPhone 5s will include the same capabilities of the other iPhone 5s models, but without a contract required. But it will only work on GSM networks. That means that using this unlocked iPhone 5s with Verizon Wireless, for example, will not be a possibility.

However, the unlocked iPhone 5s will work with AT&T and T-Mobile in the United States, according to 9to5Mac, and, in addition, this iPhone 5s version will work with GSM networks the world over without a contract.

The SIM-free iPhone 5s comes in the usual varieties, with 16GB, 32GB, and 64GB models available for purchase directly from the Apple Store online. You can still chose from silver, space gray, and gold. The 16GB model sells for $649.00, with the 32GB version costing $100 more and the 64GB top-of-the-line model coming in at $849.00. The unlocked, SIM-free iphone 5s will ship in about one to two weeks.

The Apple Store has been selling contract-free T-Mobile iPhone 5s variants since the phone went on sale, but the T-Mobile nano-SIM card would come installed with the device, and to use it contract free on any GSM carrier would still require the device to be unlocked and the nano-SIM card replaced with one that works on whatever regional carrier the user wanted. This is something that is still technically illegal, since the exemption in the Digital Millennium Copyright Act for unlocked phones was allowed to expire by the Library of Congress's Copyright Office in Oct. of 2012.

But pressure is on the wireless companies to allow unlocking devices once contracts are fulfilled from the Federal Communications Commission's (FCC) new Chairman, Tom Wheeler. In an open letter to the CTIA, a wireless carrier trade association, Wheeler asked wireless companies to voluntarily amend their industry's Consumer Code to allow for unlocked devices. Otherwise, the FCC, which has been under pressure from citizens, members of Congress, and the White House to act on the matter, will take regulatory action to force the change.

In his letter, Wheeler asked for the amendment to take affect by the holiday shopping season.

"For eight months, the FCC staff has been working with CTIA on an amendment to your Consumer Code in which this industry would address consumers' rights to unlock their mobile wireless devices once their contracts are fulfilled," stated Wheeler's public letter to the CTIA, sent Thursday, Nov. 14. The letter continued, "We are anxious to work with you and your members to resolve this matter expeditiously. Enough time has passed, and it is now time for the industry to act voluntarily or for the FCC to regulate... Let's set a goal of including the full unlocking rights policy in the CTIA Consumer Code before the December holiday season."  

Apple Inc. has provided unlocked, SIM-free iPhone 5s variants for many countries outside of the U.S., but this is the first time that configuration of iPhone 5s's have been available for sale in the U.S. Expect Apple's brick-and-mortar retail stores to begin selling the iPhone 5s, GSM SIM-free, unlocked in the coming weeks.