"[Having a suitable outfit] gives you confidence when you are going into the workplace. You look good, you feel good," he said.
The sports fan said it would feel "pretty special" wearing a suit once owned by an All Black to his job interview.
Duffie said he had a few old suits in the back of his wardrobe and was stoked to see that Working Style had teamed up with Fix Up, Look Sharp to give guys like Klomp a helping hand.
"I hope my old suit serves William well and brings some extra cheer to him this Christmas."
Working Style founder Chris Dobbs said he expected to see about 150 suits donated to the charity by the end of the promotion.
"There has been a very good response from our client. I think it's two prong – they like the idea of giving their clothes [away] and they also like the idea of stuff not going to waste."
Dobbs said some clients had traded in several suits, many of which were top-end brands including Italian fashion house Ermenegildo Zegna.
Fix Up, Look Sharp director Jane Treseder, who has a background in fashion and a social work degree, said it was great to see people like Duffie getting on board.
"Its nice for a guy like that to lead by example."
Treseder said the support of a sports star and top Kiwi fashion label also helped show men that asking for help wasn't a weak thing to do.
Fix Up, Look Sharp's pilot programme was run out of fashion label World's former store on High St in Auckland CBD, in 2014. Today Treseder styles about four job-seeking men a week at the charity's New Lynn base.
"The reason why I started the charity in the first place is because there are hardly any services just for men," Treseder said.
The charity deals with a huge range of men from those who have never worked before to others who want a career change. A lot of the referrals come from social service organisations.
Treseder said many of the men she helps out have never worn a suit before.
"Half the time they'll put that they are a small down on the size sheet but they end up being a large. They just have no idea what size they are in a suit."
She said providing the men with suitable outfits helped them feel more prepared and confident about the probability of getting a job.
"Applying for jobs is really stressful…so it's another hurdle that's not there for them."
The charity also helps equip men with the tools they need to apply for jobs including CVs.
The clothing and shoes come from a number of different places including Cambridge Clothing Company and secondhand stores such as Recycle Boutique.
You can get 20 per cent off a Working Style suit by donating an old one in store, until Christmas Eve. All trade ins are donated to Fix Up, Look Sharp.