21 Inch Drawer Slide, Full Extension, Concealed, Undermount. 563H5330B with 100 Lbs. Weight Capacity and Soft Close for 5/8 inch Thick Drawers. Including: Locking Devices (Pair)

Just what I wanted

2 of these were damaged in shipping so I called the supplier. After sending them a picture of the busted package and the damaged slide, they sent me 2 new slides out. As for the product, these are "WAY" better than side slides I've been using and while they cost a bit more, you can feel the difference every time you open and close the drawers.

The Blum under-mount drawer slides I find are the best that I have used. I took up woodworking a couple of years ago as a hobby and decided to tackle a cabinet build got on google and started to watch videos the one I liked suggested undermount drawer slides. I researched and found the Blum were highly recommended over others I tried and they are right. I didn’t know I would do quality work when taking up woodworking so as of now I have built three bathroom cabinets and a walk in closet all totaling 35 drawers with the Blum undermount drawer slides.

What can I say, it's Blum. Great fitment, great craftsmanship, top of the line in cabinet drawer slides.

Heavy duty. Worth the money. Recommended

I really appreciated how well the slides were carefully packaged for shipping. As other commenters noted, no instructions are provided but you can find that at Blum or Rockler Woodworking's websites. It should be noted that Rockler's instructions state that the slides should not be used for "retrofit" applications. However, I needed something to replace 10+ years old Grass slides on a large kitchen cutlery drawer that could no longer self-close and the drawer dimension were close to that required by the Blum hardware. Because the drawer was not constructed to specifically fit these slides, they probably do not operate as smoothly as they should. However, they work well enough and have made the drawer functional.

Prompt ship and delivery.

Worked great

Great