Purpose and key benefit These polymer rim inserts let Presta valves seat securely in rims with larger Schrader-sized holes. They provide a precise fit, protect the rim around the valve opening, and reduce valve wobble and stress during riding. Why you need them If your wheel rims have Schrader-size holes but your tubes or valves are Presta, these inserts create the correct valve seat so installation is quick and reliable. They also cushion the valve base to prevent wear and damage to the rim over time. Design and material Made from durable polymer plastic for good shock absorption and long-lasting use. Unique opening and flange design for easy insertion and correct depth in the rim; holds the Presta valve firmly in place. Classic black/red color options to match different tire and rim aesthetics. Size and compatibility Standard, one-size fit: 9 × 8.5 × 6.1 mm. Compatible with Presta valves and designed for rims with Schrader-size valve holes. Pack quantity 10 pieces per pack — convenient for multiple wheels, replacements, or carrying as spares. Performance advantages Reduces wobble and load on the rim around the valve hole. Simplifies valve installation and improves sealing stability during inflation and riding. Practical use scenarios Installing Presta tubes on older or mixed wheelsets that have larger Schrader-style valve holes. Upgrading or rebuilding wheels where you want a secure Presta valve seat without drilling or modifying the rim. Keeping a set in your repair kit for roadside fixes or as replacements during regular maintenance. Features at a glance: Function: Presta valve seating insert for Schrader-size rim holes Material: Polymer plastic Size: 9 × 8.5 × 6.1 mm Colors: Black / Red Quantity: 10 pieces Simple to install, durable in use, and useful as both a permanent solution or a spare part for maintenance and repairs.