McFly's Dougie Poynter, Tom Fletcher and Danny Jones stripped down to their birthday suits after betting fans that bandmate Harry Judd would win Strictly Come Dancing.
The trio posted a racy picture of themselves in the buff on Twitter, with only a few carefully placed props to cover their modesty.
They can be seen posing in nothing but socks and covering their manhoods with cushions and a platinum disc.
All three included separate captions with the snap, posted on their individual accounts.
I'm A Celebrity... Get Me Out of Here! champ Poynter teased fans by writing: "As promised... you pervs!"
Jones thanked fans for their support and wrote: "We said we would do it! Thanks for your votes."
A more bashful Fletcher said: "I was forced to do this... thanks for voting! Had an awesome night at @mcflyharry's little surprise bash. Lovely company."
Judd and his partner Aliona Vilani's triumph on Saturday's live final of BBC's Strictly Come Dancing prompted fans to remind the boys of their original promise.
They are no strangers to taking their kit off for a bet. Jones kept his promise to strip off for fans after Poynter triumphed on I'm A Celebrity...