Knurled Captive Screws A2 Combo Phillips/Slotted Server Rack & Enclosure 

Secure access panels easily with our knurled captive screws. Cylindrical head, combo drive, captive washer. A2 stainless steel. EMI grounding. For servers, telecom & industrial enclosures. View sizes.

Streamline maintenance and ensure reliable grounding with our **Knurled Captive Panel Screws**. Designed for industrial electronics and server racks, these screws feature a **unique cylindrical head** with the **upper portion knurled for easy tightening/loosening** and a **smooth lower portion** for a clean finish against panels. The **Phillips/Slotted combination drive** provides tool flexibility for initial installation or high-torque needs. Integrated with a **captive flat washer** and **captive spring washer** (or captive wave washer), they remain securely attached to the panel when loosened, preventing loss. Made from A2 (304) stainless steel with passivation for corrosion resistance and excellent EMI/RF shielding continuity.

Primary Uses & Applications:

    *   Server rack & data center equipment access panels.
    *   Industrial control cabinet doors & covers.
    *   Telecommunications enclosures & base stations.
    *   Test & measurement equipment housings.
    *   Medical device access ports.
    *   Aviation electronics (avionics) panels.
    *   Any application requiring frequent, tool-less access with secure screw retention and EMI grounding.

Surface Treatment/Finishes:
    *   **Passivation (Standard):** Critical for maximizing corrosion resistance by removing free iron and enhancing the passive chromium oxide layer. Maintains conductivity.
    *   **Optional: Electropolishing:** Provides a smoother, brighter finish, enhances corrosion resistance slightly, and improves cleanability/decontamination.

How to Use:

    1.  **Panel Preparation:** Install a **captive screw receptacle** (threaded standoff, PEM nut, or rivet nut) into the panel frame at the required locations. Ensure conductivity if grounding is needed.
    2.  **Insert Screw Assembly:** Insert the **captive screw assembly** (screw + captive washers) through the hole in the access panel door/cover.
    3.  **Initial Tightening (Tool):** Use a **Phillips (PH2) screwdriver** or **flat blade screwdriver** to initially tighten the screw into the receptacle. Apply sufficient torque for security and grounding contact.
    4.  **Tool-Less Operation:** For subsequent opening/closing, simply **grip the knurled upper section** of the screw head and rotate by hand to loosen or tighten. The captive washers keep the screw assembly attached to the panel.
    5.  **Grounding:** The captive flat washer ensures consistent metal-to-metal contact between the panel and the frame/receptacle, creating a reliable EMI/RF shielding path.