Princeton 5400 Refine brushes are an Interlocked Natural Bristle with a long Long Handle in a striking range of sizes and shapes. Princeton’s flagship line of interlocked bristle Refine starts with premium quality Chungking bristle and adds the panache of hand-formed interlock construction. The natural taper and curve of the bristle is expertly arranged within the hair tuft to form crisp edges and resilient points. Interlocked brushes hold their form in heavy use while other non-interlocked bristle can look more deranged than arranged. The true bounty of Refine is in its shape and size offering. Unique shapes like short filberts , extreme egberts, and sharp angle shaders usually only appear in much more expensive European ranges.