An anti-crossover nozzle with two principle pieces that snap together, having a forward end portion with a dispensing opening, a rear end portion which includes at least a pair of inlets. Each inlet has a center passage, therethrough and at least two valve leaflets biased by their own inherent resiliency...http://www.google.ca/patents/US6021961?utm_source=gb-gplus-sharePatent US6021961 - Crossover-resistant plural component mixing nozzle
