Slab bolsters, also known as Beam Bolsters, are commonly used for concrete reinforcing by providing support for reinforcing bars and meshes in order to keep them in place, as well as to prevent slumping or shrinkage.

Metal and PVC Slab Bolsters are used in reinforcing concrete structures like floor slabs, walls, columns, beams, and other reinforced concrete elements.

Comparing with reinforcing bar chairs:
Slab bolsters are typically used in slab construction, while rebar chairs are designed for vertical reinforcing bars.
Slab bolsters are available in a range of sizes and shapes, while rebar chairs typically come in a standard size and shape.

Metal Slab Bolsters types:
Slab bolster with Caps, Slab Bolster Upper, Slab Bolster with Plates

Materials:
Slab Bolsters are available in plain steel, galvanized or epoxy coated steel, or PVC.

Slab Bolster Epoxy Coated Steel
Length 5'
Heights available from 3/4" , 3", 4"
Legs spaced at 5" centers
Top wire size Gauge 4
Leg wire Guage 6
Used to support and space the bottom reinforcement steel off the form.

Slab Bolster with Bearing Plates:

Slab Bolster PVC Dipped Steel
2" Slab Bolster Plastic Dipped 5 feet
Sizes:
3/4"X5'
1"X5'
1-1/2"X5'
2"X5'
4"X5'
5"
6"
2"

Slab Bolster Upper

Slab Bolster Upper, Plain Wire, No Dipping, No Coating ( PVC dipping available)
Height: 6"
Length: Five feet
Legs spaced 5" O.C.
This metallic bar supports are mainly used to support the top steel reinforcing mesh from the base mesh

Plastic Slab Bolsters

Plastic Slab Bolster can be extended to longer lengths through the locking system.
Material: High-density polyethylene, PP
Feet that can be stapled.
Allows minimum point of surface contact with form

PP or Plasitc slab bolster provides continuous support for Rebar, Rebar Mesh, Elevated Slab, Concrete Wall Panels and Spacer chair for Walls and Columns.
Size: 3/4, 1, 1 1/4, 1 1/2, 1 3/4, 2, 2 1/2, 3, 3 1/2, 4

Plastic Bolster Chair
Plastic slab bolsters provide continuous rebar support mainly in cast-in-place slab, tilt-up and deck construction. The PP bolster chair functions well in rebar support applications, especially for stainless, black and epoxy rebar. The bolsters have an arch design to maximize strength, along with corrugations on the crossbar to facilitate positive bar location.