Replaces Part Number: 1143-120-0641, 1143-120-0631, 1143-120-0611 carburetor. Replaces Zama C1Q-S295, C1Q-S296, C1Q-S233. Replaces 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 chainsaw operation, improves engine performance, and can help resolve issues such as oil leakage, hard starting, lack of acceleration, and black smoke from the exhaust. [Excellent Quality] Made from high-quality materials. Each unit is factory tested to ensure stable engine performance, easy installation, and extended chainsaw service life. VALUE KIT: Simplify maintenance with our carburetor assembly kit. Offers great value and a cost-effective solution to keep your chainsaw running at its best. Parts are simple to install, and installation videos are widely available online. Most installations take only 510 minutes. Note: This is for the E-Z Starter version for Stihl MS251C Chainsaw. If your MS251 model has a primer bulb, this carburetor kit is compatible. Please note: Minor color variations may occur due to lighting and display differences. These do not affect functionality. Color: As Shown Material: Metal Package Contents: 1 x Carburetor Kit Package includes only the items listed above. Other accessories are not included. Note: Lighting and display settings may cause slight color differences between the image and the actual item. Measurement may vary by +/- 13 cm.