Here is the rule from the tournament site:
All participants must wear a shirt with a BUTTERFLY-type or "mock" collar (please see Team Uniform rule) and casual slacks, trousers or jeans (neat, clean and in good condition).
"Team Uniform" rule: Shirts with "mock" collars are allowed (as part of a five-person team uniform or two-person doubles team uniform) only under the following circumstances:
All five team members must have the same color "mock" collar shirt. Both doubles partners must have the same "mock" color shirt.
All "mock" collared shirts must contain a sponsor logo/message.
When wearing "mock" collared shirts, ALL bowlers must be wearing slacks (no jeans allowed).
The following list is NOT PERMITTED while competing: hats, sweats, shorts, skirts, skorts, culottes, zubas (pants with elastic cuffs).
Bowlers will be asked to change their attire if deemed inappropriate by tournament management or designee. Tournament management or designee decision shall be final.
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Lefty is the right way to be.