It's basically a pouch which is held IWB by a leather-covered spring clip. Rather than my attempting to describe it, here is the company's description:
[size=10]LCS II Concealment Holster
The LCS II ultra-concealment holster was specifically designed for the law enforcement officer, and the concealed weapons permit holder, as a comfortable, reliable and virtually undetectable in the pants holster for under-cover or backup weapons. This holster helps protect your gun from body moisture and helps to prevent the hammer or sights from getting caught in the shirt or vest when you draw. The LCS II is 100 percent handcrafted from top-grade leather and accommodates all popular revolvers with up to 4” barrels and automatics with up to 5” barrels including S&W .44 MAG. and other revolvers, SIG/SAUER, Colt, S&W, Ruger, Glock 17 and 19, Browning HP, Beretta, Taurus, H&K and Walther 9mm and.45 autos. Also Walther P-38 and P-88, Glock, S&W and Colt .45 & 10 mm, and many more.
The versatility of design allows the wearer to position the LCS II for right hand or left hand, straight draw or FBI style forward tilt or cross draw and still have a smooth, fast draw. The LCS II is and outstanding value — sturdy and comfortable for a lifetime of service and concealment.[/size]