These are three of the four sizes of the ACE car holsters, small, medium, medium plus (for Glock 26, 27, 33 or 39's, new photo to be added shortly) and large. Note that the retaining straps (also made of Velcro® hook & loop) are designed to go over the rear of the firearm and do a great job of keeping them in the holster. But this design allows you to draw through the straps without losing time unfastening them, and this really speeds up the draw considerably. Note that the adhesive mounting strip that comes with each holster is sized for the holster size it is packed with. But if you purchase an extra adhesive strip, like the one shown in the lower left corner of the picture, the strip must be large enough to accommodate the largest holster made. If you're purchasing the strip for a small or medium holster, it's obvious that you can cut it in half and get two mounting strips for the price of one! When ordering a car holster, simply specify the firearm it will be used with and we'll send you the correct size holster. The holsters come with a strip of Velcro® hook material with adhesive on the rear surface. Since the holster is constructed of Velcro® loop material, it will hold the weight of my 48 ounce M1911A-1 in an inverted position (large size holster). The adhesive will adhere to any material except cloth (like some automobile upholstery), in which case a drop of Super Glue must be added to each corner and in the center of the adhesive pad. Just make sure you have the adhesive pad positioned correctly before you press it on the surface, because you won't get a second chance. It is the "adhesive from hell!" Since the bottom of the holsters are open, barrel length on revolvers presents no problem, as the end of longer barrels will simply protrude through the end of the holster. We sell the extra adhesive strips (one is shown at the center left of this picture in front of the holster) for $3.00 so you can mount a holster in more than one location. The strip allows you to remove the holster when you leave your vehicle, boat or business and wear the holster on your belt, as each holster comes with a belt clip that can be transferred from the left to right side of the holster. All holster sizes are $19.95 plus $6.00 S&H. If ordered with a SmartCarry® concealed carry holster, there is no additional S&H on a single item. If ordered alone, add $2.50 for each additional holster, no S&H for adhesive strips ordered with a holster.