Explore the finest Diamond, Watch & Wholesale Jewelry Suppliers & Vendors in the US. Connect with our Members & Replicate In-Person Meetings Virtually. All Plumb Club members adhere to very high standards of conduct on a personal and professional level. Members are also asked to sign the Plumb Club “Code of Responsibility” annually, agreeing to uphold high standards of integrity, ethics, morals, and honesty. This enables retailers and manufacturers to collaborate in an environment of respect and integrity.