Inner Spring Cushion Replacement | Marshall Coil Spring Unit
These inner spring cushion replacements, also know as marshall spring units, are used in sofas and mattresses for a nicer firmer feel, and lasts longer than foam. They are composed of coil springs, attached with hog rings, sewn into separate pockets. The marshall coils can be added or removed to form desired size.
What Do the Cushion Unit Measurements mean?
All inner spring cushion units are measured using four numbers:
- The 1st two numbers are how many springs are in the unit and represent the length and width dimensions by number of Coil Springs.
- The 3rd number represents the diameter of the spring in inches.
- Finally the 4th number represents the height of the coil spring in inches.
So for example, a 6 x 6 x 3 x 3.5 would mean the cushion unit is 6 springs wide, 6 springs long, each spring is 3" in diameter so the unit would measure 18" x 18", and finally the unit would be 3.5" thick due to the height of the springs.
*height of outer coils may measure about half an inch taller due to inner coil tension, but should meet inner coil height after installation and regular use*
How does Gauge (GA) and Ring Attachments Affect Firmness?
A cushion unit's firmness is determined by two factors.
First is the gauge (GA). The gauge number refers to the thickness of the coils in the marshall unit. The lower the gauge the firmer the springs.
The second factor affecting firmness is the number of hog rings attached to each coil spring in the cushion unit replacement. There are two varieties, first is full ring which is firmer than the second, half ring. Full ring uses hog ring attachments on all four sides of the coils (outside coils excepted), while half ring uses hog ring attachments on two opposite sides.
Either of these two factors can affect the firmness of the marshall spring unit. For example our 15 gauge half ring is medium soft, while our 16 gauge full ring unit is soft.