Is ZSEC from out of space?? The OLSEN ZSEC stands for Zero Stack (Top 44mm) and External is Cup (Bottom 44mm). These headsets work with tapered fork steerers.
- 44mm internal top fits Zero Stack (ZS44) 1,1/8"" Top Cap
- 44mm Internal bottom fits External Cup (EC44) 1.5"" bottom cup.
- This comes in Black and No Branding and No Logos