Opteka Battery Pack Grip/Vertical Shutter Release for Canon EOS 20D, 30D, 40D & 50D Digital SLR Cameras Package Includes IR Remote Shutter Release SUPER POWER IN THE PALM OF YOUR HAND - With multiple options for battery sources and two dedicated chambers, you'll have all the power you'll ever need to keep your photo sessions rolling. ANGLED SHOOTING OPTIONS - Because the shutter release is located on the side of the battery grip, vertical shooting is not only possible but remains just as comfortable as the traditional grip thanks to a rubberized ergonomic handle. MULTIPLE POWER OPTIONS - With battery ports for both lithium-ion and AAs, you'll never be stuck with no options for power. With each battery cartridge taking four AAs, you will have more than enough power to keep the photo shoot going. TRIPOD MOUNTABLE - With a standard 1/4" tripod mount located on the underside the battery grip, attaching to any standard tripod is quick and easy. INCLUDES REMOTE CONTROL - An included infrared remote control allows you to snap pictures hands free to ensure the image is steady and crystal clear.