40-Series Solutions: separate top and bottom headset cup assemblies for tapered, reducer and conversion applications (mix & match system helps reduce inventory overlap) Same features and materials as 40-series complete headsets Top assemblies include star nut and top cap, while bottom assemblies include crown race (Carbon indicates a carbon top cover) Cane Creek Integrated 41.0mm ID (36x45), Campy Hiddenset 42.0mm ID (45x45) , ZS (ZeroStack), or EC (traditional, External Cup) available for 1", 1-1/8" and tapered steerers TECH SPECS table{border-collapse:collapse;width:100%;} td{text-align:left;padding:8px;font-weight:350;} tr:nth-child(even){background-color:#f2f2f2} th{background-color:#eb212e;color:white;text-align:left;padding:8px;} .desc .specs-heading{font-size:24px;font-weight:600;padding-top:35px;border-top:3px solid #f0f0f0;display:inline-block;border-bottom:4px solid #eb212e;width:142px;margin:0;} Model 40-Series Lower S.H.I.S. ZS49/30 Upper/Lower Lower Stack 4mm Color Black Weight 58g