These non-quick release skewers require a special Allen wrench (included) to open, thus stopping most casual wheel thieves. Sold in pairs. Extra keys are available here.
Note: compatible with frame spacing from 127mm to 135mm. Due to different spacings, you may need to trim excess off the skewer.
These are great. Good price. Not overly complicated.
Third set I’ve bought. Great quality and wicked useful.