UV arm screens for long skinny arms?

[New Horizon]

As the thread title, I have matchsticks for arms with little muscle definition, but slightly longer than 'normal'. Being redheaded, I prefer to keep my arms covered in the summer with UV arm screens, preferably black, but I haven't been able to find any that will stay up. I have some GripGrab ones which my wife has tried cinching at the top but it doesn't work (they still slide down) and it leaves the arms a little baggy. I've tried dhb, Endura and Galibier, but they are all too wide. Small or X Small might fit but they would be comically short. Does anyone know of any that might fit? I think they need to be quite stretchy, high UV resistance (50) and preferably black. Purpose made might be a solution but I don't know anyone.

 

[VinSumRox]

Castelli sp50 armwarmers - OH and I both have them, the Small size fits her slim arms, I can't get them past my elbow! Don't know if they will be long.enough though

Sigma have them on sale just now
https://www.sigmasports.com/item/Castelli/UPF-50-and-Light-Arm-2-Sleeves/14098?s=1

 

[New Horizon]

Castelli sp50 armwarmers - OH and I both have them, the Small size fits her slim arms, I can't get them past my elbow! Don't know if they will be long.enough though

Sigma have them on sale just now
https://www.sigmasports.com/item/Castelli/UPF-50-and-Light-Arm-2-Sleeves/14098?s=1

Ah, thank you. Their sizing guide is vague, based on body weight, could you possibly measure the ones you have?