Purpose and function Provides a secure fastening method when the upper hole of a dovetail plate has no internal threads. Use the screw rod passed through the cushion block under the dovetail plate and thread it into the guide ring to clamp the assembly. How it solves the problem Eliminates the need to retap or the dovetail plate when the upper hole is unthreaded or damaged. Uses existing components (screw rod, cushion block, guide ring) to restore a strong, reliable connection. Key benefits Simple installation: feed the screw rod through the cushion block beneath the dovetail plate, then tighten into the guide ring. Secure hold: the guide ring (which normally includes screw holes) receives the screw rod for stable clamping. Cost‑effective : avoids machining or replacing parts by using standard fastener routing. Compatibility and attributes Function: converts an unthreaded upper hole into a threaded connection via the guide ring. Compatibility: works with dovetail plates, cushion blocks and guide rings designed to accept a passed screw rod; confirm matching screw diameter and thread engagement on the guide ring. Size and fit: ensure the screw rod length and diameter match the assembly clearances and guide ring screw holes. Material and performance: performance depends on the materials and thread condition of the guide ring and screw rod; use appropriate hardware for required load and environment. Installation tips Verify the guide ring has screw holes or a receptive thread before assembly. Select a screw rod of the correct diameter and length so it fully engages the guide ring threads without bottoming out. Use the cushion block to distribute clamping force and protect the dovetail plate surface. Typical use scenarios Field of a dovetailmounted component when the upper hole cannot be tapped: route the screw rod under the plate through the cushion block and secure into the guide ring to restore function without replacement. Retrofitting or adapting older dovetail assemblies that lack factory threads: create a reliable connection using the guide ring's screw holes. Quick assembly of clamped fixtures where access to the of the dovetail plate is limited: pass the screw rod beneath the plate and tighten into the guide ring for a compact, stable setup.