Lauren Price is preparing to swap her world championship belts for a Tŷ Hafan volunteer's badge.
The Bargoed boxer will be helping the children's hospice to celebrate the 30th anniversary of its Caerphilly charity shop by doing an hour behind the till.
The Market Street shop opened on 14th July 1995 as part of fundraising efforts leading up to the opening of the Sully hospice in 1999.
Price became the unified welterweight world champion in March after beating Natasha Jonas at London's Royal Albert Hall, and says she's looking forward to serving as many customers as possible between 10am and 11am on Monday morning.

The day of celebrations will include Caerphilly mayor Dawn Ingram-Jones paying a visit while children from a local school will have 30 unique butterflies displayed in the shop window.
Mel Sage, Tŷ Hafan's head of retail, said: "We are so excited to be able to welcome Lauren and Cllr Dawn Ingram-Jones to our shop in Caerphilly to help us to mark this wonderful occasion."
"Our Caerphilly shop was one of the very first Tŷ Hafan charity shops to open and is now our oldest shop still in operation."
"It has been both our pleasure and our privilege to serve the community of Caerphilly for the past 30 years and income raised by local people donating to and buying from this store has enabled Tŷ Hafan to support children with life-shortening conditions and their families since our hospice first opened in 1999."

Residents in Cardiff and Vale offered free access to nutrition and fitness app
Heart Charity encourages Half Marathon runners to make heart health part of their preparation
“More than just a sport”: Minister for culture and sport questioned on future of rugby in Wales
Fraud Warning Issued Over Scam Calls Targeting Patients
Councillors approve plans for over 300 new homes in Rhoose
Penarth school project sparks Welsh language transformation
South Wales and Gwent Police introduce new online portal for crime victims
Penarth Pier Pavilion Cinema awarded £65,000 for major equipment upgrade
New Cafe could be coming to High Street, should plans be approved
Reform MS Sarah Cooper-Lesadd has defected to Plaid Cymru
Public sector broadcasters facing “huge challenges”, according to Wales’ culture minister
Welsh Government Plans 30% Rates Cut for Hospitality and Leisure Businesses
Loan scheme to help bring landmark Cowbridge building back into use
Women less likely to receive lifesaving CPR as Calon Hearts calls for more realistic training
Shortlist announced for 2026 Vale and Bridgend Business Awards
Vale Council to Consider Changes to Recycling and Waste Services
1,000 children vaccinated against Hepatitis A in Barry but there’s still time to protect your child
Plans have been approved to convert offices into a bedsit in Barry, despite police concerns
Police Appeal for Witnesses after Penarth Road collision