We have a narrow cupboard that has until now proved quite useless.  We could only use the first row or two as reaching anything in the back was a nightmare.  These glide with ease and make it possible to see and reach items that would have been in the back of the cupboard with ease. It's increased my shelf space even though it did narrow the shelf a bit as I can finally use the self all the way to the back.  It was also a lot cheaper than the $5,000 we were quoted for a gliding pantry cupboard which I thought was ridiculous.  It was pretty easy to install as well.  Basically I would highly recommend this product, which is good as I bought three of them.