The Tec-9 | Red Quartz skin was added to Counter-Strike: Global Offensive in the Operation Bravo case released on September 19, 2012.
This skin features a red and black geometric quartz pattern over the whole gun. The pattern has angles and shapes of different sizes.
As one of the older skins in the game, the Tec-9 | Red Quartz remains a relatively popular and affordable skin.