Product description from http://www.spigen.com/collections/galaxy-note-4
Galaxy Note 4 Case Neo Hybrid
The Neo Hybrid® for the Galaxy Note 4 is a completely reimagined dual bumper case that provides full coverage of your phone. It is composed of a hard polycarbonate frame and a soft TPU cover. The frame is rounded with a reinforced base for durability while the TPU casing has a textured midsection for grip and style.
Galaxy Note 4 Case Neo Hybrid Metal
The Neo Hybrid® Metal for the Samsung Galaxy Note 4 consists of a premium diamond-cut® aluminum frame and anti-stretch TPU that delivers premium quality and secure protection. The metal buttons include an inner protective layer to prevent scratching on the device’s buttons. The TPU casing has a textured midsection for grip and style.
http://www.ebay.com.au/itm/Galaxy-Note-4-Case-Genuine-SPIGEN…
Galaxy Note 4 Case Slim Armor
The Slim Armor® case for the Galaxy Note 4 provides complete all-around protection while maintaining a slim profile. The double layers of rubberized TPU and hard polycarbonate provide protection in a form-fitted design. The buttons are now flush with the case with embossed glossy symbols for a refined look and comfortable experience.
http://www.ebay.com.au/itm/Galaxy-Note-4-Case-Genuine-SPIGEN…
I can vouch for neo hybrid (non metal) my kids have dropped my phone down the stairs, on tiles, I've bounced it off the cement footpath. Even the case has barely a scratch on it. But hten I paid under $10 on ebay a few months ago.