I have a new Stan's No Tubes Neo E-Sync left, non-drive side hub end cap for sale. This is a 10 x 135mm QR, quick release compatible rear end caps. Do note this is for one left, non-driveside end cap. Below are the specs from Stan's website. These end caps fit 6-bolt E-sync hubs with 10x135mm quick-release rear
axle spacing and Shimano HG or SRAM XD/XDR cassettes. The non-drive side
end cap includes a low-friction U-cup seal that snaps into place and
stays secure even when your wheel is removed from your bike. Compatible
with E-sync, Neo, and Neo Ultimate 6-bolt 10x135mm quick-release hubs
and Shimano HG or SRAM XD/XDR freehubs. Not compatible with any
Centerlock hubs. Not compatible with 142mm, 148mm, 157mm, or
single-speed E-sync and Neo hubs. Not compatible with Shimano Micro
Spline hubs. Not compatible with M-pulse hubs. See photos for details. I will offer free shipping to the Lower 48 states only. Alaska and Hawaii buyers may pay additional shipping charges. All sales are final. Returns are not accepted. Please email me with any questions prior to purchasing. Thank You!