Exell A21PX 4.5V Alkaline Battery – Replaces Eveready 333, 523, PX21, PC133A – Fits Mac Plus, Electro-Voice Mic, Polaroid Flash, GE Radio, Smoke Detector, Vintage Electronics

This battery is not available in Japan, so I am very happy to have been able to purchase it.

Counter to another reviewer's experience, this battery fit the Macintosh Plus's battery compartment perfectly, and is the exact same height as the original Energizer 523. Perhaps the other reviewer's metal contacts were bent due to age. It does indeed appear to be three 1.5-volt half-AA batteries heat-shrink-tubed together, which is fine.

Doesn't have a full charge, but given the age at least it works. My 1986 Macintosh is working again. Hopefully it lasts a while.

I have an old Electro-Voice condenser microphone that needs this special 4.5v battery. I used to get Eveready's but they no longer make them. This battery works very well, and has brought my old microphone back to life.

This battery is advertised as replacing a type 523 battery. I have a piece of rack gear for music that has an internal battery to save settings and this is supposed to replace it. It is the correct width, but the length is off and doesn't make contact with both ends of the clip it snaps in to. Even with pushing the ends of the tabs together or by wedging something metal in to make contact, it still doesn't work. My volt meter shows it dead and I just got it yesterday.

It's fine

This is not what I wanted.

I found an original Macintosh in storage and decided to restore it.After searching on various restoration forums and reading reviews I came to the conclusion that this was the best replacement for the Energizer power cell that runs the internal clock in the back of the machine.While some people reported that the cell did not fit their particular machines, it fit mine, which is the original Macintosh model.