Compared to a lot of bands I have worked with,' says Tommy Whitelaw. 'U2 put a lot of time into the quality of their merchandising. What we are selling on tour is what they have selected from many more items.'

Whitelaw, Merchandise Road Manager with Deluxe, the company who produce U2's tour clothing, has been selling t-shirts on the road with rock bands for more than a decade. He has noticed how times - and the fans - have changed.

'I was brought up to go to a gig and buy the t-shirt and put it on straight away.' he says. 'I can remember doing Iron Maiden shows and you'd watch as the fans arrived, headed straight for the stalls, bought the new t-shirt and put it straight on - on top of the Iron Maiden shirt they were wearing from the previous tour!'

These days fans are more sophisticated. 'At shows with many bands today, fans race in to buy their shirt and then they pop it carefully in a carrier bag to take home afterwards.'

Not so with U2 fans he adds, which is one of the reasons he is enjoying the Elevation Tour so much. 'I love being on the road with this band because their fans are so committed. They're so proud of this band, they want the shirt on straight away.'

Tommy has managed the merchandise with everyone from Iron Maiden to The Verve, The Spice Girls to Elton John - unloading the vans, standing behind the counters, monitoring the stock flow, packing it all away and then driving to the next show. Travelling the world, with even the greatest rock band, is maybe not quite as romantic as it sounds. The day we spoke he had been up at 8.30am to prepare for the evening show - but had not hit the sack the previous night until 5.30am. Less than three hours shut eye.

'This was a slightly odd day,' he says. 'Normally I'm at the venue by 10.30am and then, when when we are playing in a venue with 20,000 fans. I'm managing up to 60 people over the course of the day.'

This time around U2 have about 27 items on sale, including 7 different t-shirts, hooded sweats and embossed Levi jac kets to luggage tags, button badges and tour programmes. Everything is proving popular with different parts of the audience. In contrast there can be tours with some bands which are 'soul destroying' because the fans are not that committed and the product is 'hard to shift'.

But no fans are more committed than those of U2 - you can even measure their commitment by the volume of sales over the course of an evening. With many bands he says, you mould sell three quarters of your product before the band come on stage but on Elevation 2001 it is less than half of that. Instead there is a great rush to buy at the end of the show.

'The reason for this is that the most hardcore of U2 fans arrive at the show and just want to get as good a place as they can right down at the front of the gig, ideally in the heart. 'They are the ones who come and see us to buy their stuff after the show.'

And he is excited about plans to bring out new lines as the tour progresses. In preparation for the Slane Castle shows, two new 'event' t-shirts have been produced. If you didn't get a ticket for the show, you can always buy the t-shirt one online from U2.Com ! We'll have the news ones up soon.