Absolutely solid and can take a load of weight. Used them to suspend my tablesaw in my work bench so needed something dependable, these so far haven_ let me (or the furiously spinning blade of doom) down.One slider has a locking lever that is easy to use as long as you give the sliders the advised opperating spacing. This is set out in the pictures on the selling page and in the installation paperwork.I didn_ recieve the paperwork with my purchase however the seller sent it across via email within 24hours.If you have something heavy you want held up, these will do the trick.