Instruction: Given a question and the related document, and generate the answer to the question based on the information provided in the document.

Input:
Question: how long will the batteries last
Document: I use rechargeable AA batteries, and now I can take a pocket full of them with me and shoot all day, never worrying about when the battery brick will suddenly give up the ghost. The adapter seems a little pricy for what it is, but it works well and will last as long as I don't get too anxious getting out of the PIB battery slot. :-)
Pack this baby with four Energizer Ultras, put a 32 GB SDHC in the camera, and try to fill 'er up! I haven't had this setup long enough to tell you by how many times it outlasts the rechargeable batteries. I can only tell you that it's a lot. If you have ever turned a camera on and off, nursing a dozen last shots from a dying battery pack, you will appreciate what the Energizer Bunny (and this battery holder) can do for you.
Many people buy the cheaper alternative brands of this product, but I feel the Pentax brand is better built and may last longer.
I bought this in case I was unable to charge my other batteries--it is great for travel because I should be able to find batteries anywhere.
Good alternative, although it is rather expensive as an alternative for the Pentax replacement Lithium-Ion batteries also available on amazon
So handy, if the square type battery depletes, it's nice to be able to use this to slip in 4 AA batteries and keep snapping photos.
One of the things I like about Pentax is the fact you can use AA batteries; but unfortunately they changed that with the Kr unless you buy an adapter.
It works great but with the batteries you don't have a full load. But AA bateries are for sale everywhere. With the limitations it is a good product, I would recommend it.
Fits right in the battery slot, powers the camera with AA batteries. Great. One of the reasons I chose a Pentax camera.
The item allows me us use double A batteries during emergencies with my camera. It is wonderful to have another power supply when you cannot recharge your batteries.
Answer: Not being a jerk, but it depends on what you buy...