One of the most cheapest but best economic upgrade for your camera
I just bought a Canon 5DSR to use in addition to my 750D. Now I would go out with my 750D and nearly always had to change the battery. Now the 750D wasn't bad as it's a lot smaller to the 5DSR so you can flip it and replace the battery no problem. Not so much with the 5DSR, especially when you have a monopod and telephoto lens fixed to it! The easiest solution is the battery pack. Although this was a second hand unit, it was kept and presented well in its original packaging, every thing was there and now it's a permanent fixture to my 5DSR. A must have, at a bargain price!!