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Affiliate links · Last verified 2026-05-21 · 🌍 Outside the US? Amazon and eBay will redirect you to your country's local store automatically.
The Story
Two sisters from Bonville, ON, bring a unique type of underwear to the Den.
The Pitch on Dragons' Den Canada
Tri-Sis Underwear appeared on Dragons' Den Canada (Season 4, Episode 17) in 2010. Marilyn McMahon-Ayerst & Brenda Dawson pitched the product to the Dragons. Asked 250K for 30%.
Where they are now: Outcome not recorded on CBC archive.
Frequently Asked Questions
Is Tri-Sis Underwear still in business?
Outcome not recorded on CBC archive.
Who founded Tri-Sis Underwear?
Tri-Sis Underwear was founded by Marilyn McMahon-Ayerst & Brenda Dawson.
Did Tri-Sis Underwear get a deal on Dragons' Den Canada?
Yes — Asked 250K for 30%.
Where can I buy Tri-Sis Underwear?
Tri-Sis Underwear is available on Amazon and eBay. We compare current prices across both at our /results page — link below.
Related from Dragons' Den Canada
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