1M4 ..I am currently looking for data/data sheet for this item.

Probably RTL probably 1965 date lot nr.
NOTE: all these devices have one cut lead..whether that is by design or not I
dont know.

I have 18 of these flat packs.

NOTE I bought these from an old timer who had a number of interesting old
parts.

The little box they were in was labelled UL925
DT (mu) L 95051-846 (greek letter mu is something like U and I believe Fairchild used this greek
letter in their part numbers.
DT(mu) L 94651 - this is another IC (DIP) that uses the mu greek letter in the part nr. -- the F for Fairchild .
The SN524ALs that I have (4 of them) are used pulls that I have not tested.
These are used pulls
I have one MC1690S
i HAVE ONE --- F for Fairchild 715HC
I have 2 of these ul 923 flat packs

The actual part nr on the chip is
1M3 I believe..it is a bit hard to
read.
these 2 923s on the red
plastic holders have been
sold. Dec 2012.
I have 10 of these now available ul914 types that are branded with ML20A  (S for Signetics perhaps) date/lot 6919