This is a throttle stop screw & spring to adjust tickover speed on the Weber DCOE range of carburettors. DCOE, DCO/SP, DGAS, DGMS, DGV, DGAV, DMTL, DMTR, IDF, IDA, DCD, ICH, DCNF, DRT, DFM, DFV, TLDM, DFT, DIR, DFEV, TL, DRTC, DFTH, IDAP, ICEV & many more.