Replaces Part Number: 1143-120-0641, 1143-120-0631, 1143-120-0611 carburetor. Replaces Zama C1Q-S295, C1Q-S296, C1Q-S233. Replace for Walbro WTF-9 carburetor. Air filter tune-up kit for Stihl MS231, MS231C, MS231Z, MS251, MS251C, MS251CBE, MS251C-BEQ, MS251Z chainsaw (Primer Bulb Type). [] This carburetor kit helps ensure smooth operation of your chainsaw, improves engine performance, and effectively addresses issues such as oil leakage, difficult starting, lack of acceleration, and black smoke from the exhaust pipe. [Excellent Quality] Made from high-quality materials, each carburetor kit is factory tested to ensure stable engine performance. Designed for easy installation and built to extend the service life of your chainsaw. VALUE KIT: Simplify maintenance with this carburetor assembly kit. Offers great value as a cost-effective solution to keep your chainsaw running at optimal performance. Parts are simple to install, and installation videos are readily available online. Typical installation time is 5–10 minutes. Note: This kit is designed for the E-Z Starter version of the Stihl MS251C chainsaw. If your MS251 model has a primer bulb, this is the correct carburetor kit. Please note: Slight physical color variations may occur due to lighting and display differences. These variances do not affect functionality. Color: As shown Material: Metal Package Contents: 1 x Carburetor Kit Note: The package includes only the items listed above. Other products are not included. Due to lighting and display settings, the actual color may vary slightly from the image. Measurement may vary by +/- 1–3 cm.