Using shelf pins is one of the most common ways to make adjustable shelves, but they do have at least one downside — if the shelf isn’t exactly flat or the case is racked, the shelves might not contact all four supports, leaving you with a shelf that rocks — and not in a hip way.
Spiral Supports fit in the same holes as 5mm shelf pins and use a unique method to make sure all four supports always contact the shelf. If one support isn’t touching the shelf, just use a flat blade screwdriver to turn the support clockwise until the shelf is stable. Another advantage of these Spiral Supports is that you can use the supports to raise or lower the shelf — albeit by a small amount.
The Spiral Supports are available in clear, white, light brown, dark brown, and black. For $6 you can buy 25 clear spiral supports at Woodcraft; otherwise you can purchase 15 Spiral Supports for $7 on the corporate website.