(19 May 2016, 3:26 pm)South Tyne Lad wrote There Euro 4, Only Solo's that are Euro 5 are Darlington's 11 Reg ones and the 59 Reg ones might be Euro 5 too.
If you check the NEB fleet list for Arriva, you will find that the 08 & 58 reg Solos are Euro 5.