The group are wrapping up 2011 by playing the O2 ABC in Sauchiehall Street tomorrow night.
The show, in front of almost 1400 fans, will be the quartet's biggest in the UK – but comes hot on the heels of the band playing to more than 1000 people in New York.
"We don't really get nerves, but before that New York show our dressing room was upstairs, above the stage" recalls Jetpacks drummer Darren Lackie.
"Five minutes before we were going on we looked out the window and thought, 'That's a lot of people -' It was more excitement than nerves, though. There was just a silly amount of people there.
"It was great, we have also started to step it up a bit with our playing. When you have that many people coming down to see us – and we're not stupid, we know our reputation as a live band – so we were conscious of wanting to put on as good a show as we can."
The group's Stateside success saw them mentioned by a pundit on American sports show Around The Horn, and they were invited to appear on late night chat show Last Call With Carson Daly, which airs on the NBC network.
That means Jetpacks are enjoying major success in America, and Darren believes it is partly due to the amount of TV exposure alternative bands can get in the USA.
"There's a lot of support for rock and alternative bands over there," he says.
"Over here, I can't think of any show that would put on a band like this, other than maybe Jools Holland, and that is not the easiest to get on.
"But in America there are so many of them, and one of the bands supporting us, Royal Bangs, had just done Jimmy Fallon's show, so it is not just big bands that everyone knows, which is what happens over here."
If anything will help Jetpacks gain equal exposure back home, it is their thumping second album, In The Pit Of The Stomach, released through top indie label Fatcat Records.
It is thrillingly noisy and is a collection of songs that achieves a more consistent, louder tone than the quiet/loud approach of debut album These Four Walls.
"We are a lot prouder of the second album than the first," says Darren.
"We got it exactly how we wanted it to sound. When we recorded the first album the whole thing was pretty much live. We didn't have a lot of time in the studio, it was very rushed and we didn't know what to do, or how to really get our opinions across to the sound engineers."
The drummer believes that new-found confidence will pay off at their live gigs, which have already been praised for the ear-splitting noise the band concoct.
"With this album, we just wanted to write a loud, fast, fun rock album that would be fun to play live, and would be fun for people to listen to," he says.
"We just wanted a big, in-your-face rock album. There isn't a song on this album that isn't fun for me to play ...
"We wanted this to be a record we really enjoyed playing live.
"There are some songs on the first record we don't play anymore, because they are a bit boring, but with this one we are happy to change the set around every night because we are happy to play all the songs on this album."
Given the band's success and growing reputation, it's possible they could follow their former label mates Frightened Rabbit, who jumped from Fatcat to the major Atlantic Records label. And Darren admits he would be tempted if a big label came calling.
"It would be silly to say no to a major label," he says.
"But we are happy at Fatcat, though – it is a nice indie label where it is like a family."
l We Were Promised Jetpacks, O2 ABC, tomorrow, £12, 7pm.