Waterproof mahjong tilesCommunity‑charity‑fundraisers‑hosted‑in‑Tulsa‑sometimes‑feature‑fun‑mahjong‑tournament‑competitions‑with‑low‑cost‑event‑entry‑fees‑whose‑collected‑fund‑proceeds‑get‑donated‑toward‑worthy‑local‑non‑profit‑charitable‑organization‑projects.