The Xtrucase for the iPhone 4 and iPhone 4S is a CNC machined slider style case crafted from Swiss imported aircraft grade aluminum. I will be doing a full review and giveaway for the Duo-Slider and the Slider.
Full review here.  
More and 20% off any case after the break.

The Slider and Duo Slider have an on/ off button designed into the case. The interior of the cases are lined with a shock absorbing material that will help protect the iPhone in case of a drop and create a nonconductive barrier to help maintain the cell signal. The cases are available in a verity of colors and finishes.The cases will come with a front and back screen protector to protect the iPhone. Xtrucases is having an introductory offer now for free shipping on your initial order with this code ( intro2012 ). 
I will be posting the full review on 2-10-12 but untill then I have a cupon code to share with all my viewers it will give you a 20% discount on any order from XTRUCASE the code is  igadgetgeek 
Bellow are some photos of the cases and some colors.