Just found this on a different website hope all this explains your questions
CB 27/81 - This is the original legal stamp for UK CB Radios. Introduced in 1981, the CBs with this stamp are only legal to use in the UK. Using FM and consists of the 40 channels we know and love, the 'muppet' band. MPT1320 is another stamp of the exact standard.
CEPT Mid Band Europe CB Band
CEPT - The European CB Radio band, or in the UK, MIDBAND. Radios carrying this stamp are legal to use both in the United Kingdom and Europe. Many older 27/81 sets have over the years been modified to have MIDBAND aswell as the UK 40.
PR27/94 Moden Lega Stamp.
PR 27/94 - The newer model radios from 1994 carried this stamp. It uses the exact same UK Channels as the 27/81 Cb Radios but tougher conditions set by the home office meant these radios had narrower filters, making them thin sounding, quieter and generally less efficient to the Breaker.
PR27/97 or MPT1382, the dual cb band standard stamp.
MPT 1382 or PR27/97 - The late nineties stamp that basically combined the CEPT and PR 27/94 for use on 80 channel dual band radios. Radios bundled with this stamp are legal only in this country, and cannot be used in Europe as the unit contains the offsetted UK CB Band.
EC Multiband CB Radio
European Multi Standard - Most radios bought today are usually all European Multi Standard. This is a system were by upon switching on your radio, the CB will ask for your country. Once you select the country, the radio would then operate according to that countries legal CB bands. Ideal for truck drivers who drive accross the continent, if only the truck drivers still used the CB, a tiny fraction still do, but most do not thanks to mobile phones and sat navs.
And the UK/EU button switches frequencies to comply with EU laws if you ever go out of the UK
hope this helps you out a little
