Curtain Rail End Cap

End cap for curtain rails of this style:

https://www.mitre10.co.nz/shop/sullivans-extendable-hand-drawn-s2-curtain-track-set-1200mm-to-2000mm-ivory/p/214962

the originals don't work very well (they pop off the end and half the curtain comes off with it). If you get the scale right, these work much better.