Multiquip 21611 Screw THP 1/4-20 x 5/8 SS

The Multiquip 21611 Screw THP 1/4-20 x 5/8 SS is a genuine OEM fastener designed for Whiteman ride-on power trowels including HTX44K4, HTX44K5, HTX44Y4, HTX44Y5, STX55J6, STX55Y6, STXD6i, and HTXD6i models. As a direct OEM replacement, part 21611 meets the original design specification for thread pitch, head profile, and stainless steel grade — ensuring a secure, correctly torqued installation every time. Sourced directly through authorized Multiquip channels, this fastener is the exact screw called out in the OEM parts documentation for these hydrostatic trowel series.

Key Features

• Stainless Steel Construction — Grade stainless steel resists corrosion and surface degradation in demanding concrete finishing environments.
• Correct Thread Specification — 1/4-20 thread form and 5/8-inch length match the OEM-specified engagement depth for a flush, rattle-free fit.
• Genuine OEM Part — Manufactured to Multiquip's original specification, so thread form, head profile, and material grade are exactly what the machine was built with.
• Broad Hydrostatic Trowel Fitment — Confirmed for HTX44K4, HTX44K5, HTX44Y4, HTX44Y5, STX55J6, STX55Y6, STXD6i, and HTXD6i ride-on power trowels.
• Structural Integrity Under Vibration — A correctly sized and properly torqued fastener maintains panel and guard alignment during high-cycle troweling operations, where loose hardware can cause component wear or safety hazards.

Fasteners like the Multiquip 21611 Screw THP 1/4-20 x 5/8 SS are the hardware that keeps guards, panels, and structural components firmly located on ride-on power trowels. The stainless steel material resists the moisture and alkaline exposure common on concrete finishing jobsites, where carbon steel hardware would corrode and seize over time. Using the correct OEM fastener — with the right thread pitch and length — ensures components stay torqued to spec and do not work loose under the continuous vibration generated during troweling operations.

Part Details

Compatibility & Fitment

Verify Before You Order

Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.

Why Buy From DHS Equipment

Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.

Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.