Rainbow TOS 1.4 for Atari ST/STF/STFM & Mega ST computers. New in 6 chip OTP version. 

Picture is of a typical set.

We have some sets from Atari that have different labels and or chip types that are from different production runs.

No soldering required if you replace with a 6 chip TOS 1 or 1.2 with a 6 chip TOS 1.4. Picture shows both sets but this auction is for the 6 chip set only. 2 chip TOS sold out at this time. The installation instructions are provided at links below. You can switch from 2 to 6 or 6 to 2 by changing the solder jumpers and installing sockets(IF they were not installed originally). Read Instructions and check your ST. 

Take computer apart, remove old TOS, insert new TOS and just put it back together. Many improvements and bug fixes.

Only requires phillips screw driver, needle nose pliers plus a tool to remove the old TOS(I use a flat blade screwdriver).

Shipping weight is estimated to be 8 oz.     

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