T-Mobile has announced a new promotional offer for Apple users. 

The United States-base mobile carrier is allowing customers to exchange their iPhone 6 for Apple's new iPhone 6S free of charge, Business Insider reports. 

"When you order your upgrade during the first 48 hours it's available, we'll give your order priority and ship it first, along with others who qualify for priority access.," T-Mobile officials wrote in an announcement promoting the deal. 

"So you'll be among the very first to get your brand new phone when we have inventory."

The offer is only available through the company's Jump on Demand deal, which allows customers to make monthly installment payments of $15. It also requires that current iPhone 6 phones traded be in good condition and that users upgrade by the end of 2015. 

Apple is set to release the iPhone 6S. Its specs include a 4.7-inch screen, 16GB of storage and an improved camera. It has also been reported that the new mobile device will include Force Touch capability. 

A reversible USB connector has also been speculated for the iPhone 6S.