ROMs are identical for ZX Spectrum+3, +2A and +2B.

Rom 0	128k Editor
Rom 1	128k syntax checker
Rom 2	+3 DOS
Rom 3	48k Basic

There are 3 versions:

	Version 4.0
	Version 4.1
	Spanish version
	
	
How to test whether you have ROM version 4.0 or 4.1:

in +3 Basic enter:

    print peek 19		--> 167 = v4.0		--> 255 = v4.1
    print peek 20		--> 255 = v4.0		--> 21 = v4.1

Peek seems to peek in ROM #3.


my tested specimen:

ZX Spectrum +3,  made in Taiwan, E016940: Version 4.0
ZX Spectrum +3,  made in Taiwan, U109131: Version 4.0

ZX Spectrum +2A, made in Taiwan, no ####: Version 4.1
ZX Spectrum +2B, made in China,  S077463: Version 4.1