PlateSelect RNAi duplexes (Invitrogen Corp., Carlsbad, CA) offer the ability to customize 96 well-plates with the company’s chemically modified Stealth or standard BLOCK-iT RNAi duplexes. Customers develop customized plates using an intuitive Web interface, and they can order anywhere from one to 96 different duplexes in a single plate. RNAi duplexes are synthesized on demand and are provided at 1 nmol/well in the well orientation that a customer chooses. The duplexes arrive in ready to transfect format and are synthesized based on algorithms designed to reduce the chances of off-target effects.