Oatey K835-10 Flush Valve Flapper 3.5 Inches

Product Description

The OATEY K835-10 is a 3.5-inch flush valve flapper assembly designed to reduce water consumption in residential and light commercial toilet installations. It features an adjustable water-saving flapper paired with a timing cone that controls flush volume and duration. This replacement part is suited for licensed plumbers and experienced DIYers performing toilet maintenance or water-efficiency upgrades. The flapper is sized for 3-inch flush valves with a 3.5-inch to 8 NPS thread diameter, making it compatible with a range of standard toilet flush valve bodies.

This flush valve flapper is intended for use in residential and light commercial toilet systems. It is a direct replacement option for toilets manufactured by American Standard, Kohler, and Eljer, as well as any toilet equipped with a flush valve of similar thread size and configuration. It is commonly installed during routine toilet repair, flapper replacement service calls, or as part of a water conservation retrofit. The adjustable design allows the installer to fine-tune flush volume to meet local water-use requirements or owner preferences.

Key Features

• 3.5-inch flush valve flapper sized for 3-inch flush valve bodies
• Timing cone included for adjustable flush volume and duration control
• Water-saving design helps reduce per-flush consumption
• Compatible with 3.5-inch to 8 NPS thread flush valve configurations
• Sold as a single unit for one-at-a-time repair or replacement

Compatibility

Designed for use with American Standard, Kohler, Eljer, or any flush valve with a similar 3.5-inch to 8 NPS thread size.

Installation Notes

Installation is typically performed by a licensed plumber or qualified service technician. Shut off the water supply valve at the base of the toilet and flush the tank to drain residual water before removing the existing flapper. Inspect the flush valve seat for mineral buildup or damage before seating the new flapper. After installation, adjust the timing cone to achieve the desired flush volume and verify the flapper seals completely to prevent running.