Hp 25 LED brightness

[GreyUser]

You’ll typically find the difference in the lcd display itself. HP sorted them by intensity and used the lower intensity units primarily in the low cost 21. It would not surprise me to learn they went into 25’s when volumes went up.

The 5 digit bubble displays used on the classics had a brightness code letter printed on the back of the package. This wasn’t needed with the Woodstocks since it was only one unit but they absolutely had brightness variations in the individual led chips, wafer to wafer.