Built-up lettering is made from two identicle lettering shapes connected by a "return" which is precision made to fit the lettering shapes' edges, this gives them their 3D look. The returns can be any height but are mostly, for practical reasons, between 80mm - 100mm in depth.

They are often manufactured from stainless steel or acrylic because both materials are flexible enough to bend easily when used to create the returns and can withstand an outdoors environment. Stainless steel built-up lettering can be spray coated or coloured acrylics can be used to match corporate identities, both can be backlit using flourescent tube lighting or LEDs.

Acrylic & Metal Built-up Letters - at a glance: