Although red Cellulose Acetate Butyrate (CAB) (generally known trade names are Cellidor, Tenite and Tenex) scaled Swiss Army Knives are most common, there are many colors and alternative materials like more resilient nylon and aluminum for the scales available. Many textures, colors and shapes now appear in the Swiss Army Knife. Since 2006 the scales on some knife models can have textured rubber non-slip inlays incorporated, intended for sufficient grip with moist or wet hands. The rubber also provides some impact protection for such edged scales. A modding community has also developed from professionally produced custom models combining novel materials, colors, finishes and occasionally new tools such firesteels or tool 'blades' mounting replaceable surgical scalpel blades to replacement of standard scales (handles) with new versions in natural materials such as buffalo horn. In addition to 'limited edition' productions runs, numerous examples from basic to professional-level customizations of standard knives – such as retrofitting pocket clips, one-off scales created using 3D printing techniques, decoration using anodization and new scale materials – can be found by searching for 'SAK mods'.