Concealed Fastener Systems NS-100 NS-100 1″ NAIL STRIP CONCEALED FASTENER SYSTEM Low-profile panel clipless system for fast and easy installation. SL-150 SL-150 1.5″ SNAP LOCK CONCEALED FASTENER SYSTEM Integral interlocking system with clip attachment SLZ-150 SLZ-150 1.5″ SNAP LOCK Z CONCEALED FASTENER SYSTEM A nail strip combined with snap lock system, clip attachment gives strength, smooth appearance with easy installation features. QM SOFFIT QM SOFFIT PANEL CONCEALED FASTENER SYSTEM Designed for wall, fascia, liner and soffit applications where a flat smooth appearance is required.