SPI Finish Standards

The SPI Finish Standards refer to the surface finish standard set by American SPI (Society of the Plastics Industry). The standard covers 12 SPI surface finish grades and features at:

  • from SPI A1 to SPI D3 ( RA 0.012 μm to RA 18.00μm).
  • from shiny to dull.
  • from polish to texture.

At below SPI finish chart, we use surface roughness Ra (μm), finishing methods, steels suggested as references to show each grade’s finish.

If you want to check what the physical surface finish would look like, the best way is to get our SPI Finish Card.

SPI Finish StandardSurface Roughness Ra (μm)Finishing MethodFnishing LookSteels Suggested
SPI A10.012 to 0.0256000 Grit DiamondSuper High Glossy finishS136 (54HRC) or 8407(52HRC)
SPI A20.012 to 0.0253000 Grit DiamondHigh Glossy finishS136 (54HRC) or 8407(52HRC)
SPI A30.05 to 0.101200 Grit DiamondNormal Glossy finishS136 (300HB) or 718H
SPI B10.05 to 0.10600 Grit PaperFine Semi-glossy finish718H
SPI B20.10 to 0.15400 Grit PaperMedium Semi-glossy finish718H
SPI B30.28 to 0.32

320 Grit PaperNormal Semi-glossy finish718H
SPI C10.35 to 0.40

600 Grit StoneFine Matte finish718H
SPI C20.45 to 0.55400 Grit StoneMedium Matte finish718H
SPI C30.63 to 0.70320 Grit StoneNormal Matte finish718H
SPI D10.80 to 1.00

Dry Blast Glass BeadSatin Textured finish718H
SPI D21.00 to 2.80​Dry BlastDull Textured finish718H
SPI D13.20 to 18.0Dry BlastRough Textured finish718H

SPI Finish Card

Plastopia provides the plastic SPI Finish card at palm-size to give you a useful guide on SPI Finish Standard. 

Compared with traditional metal plaques, plastic cards give you a real hand touch or visual polish finish of your plastic parts. You will see exactly what you will finally mold.

SPI Finish Card

The card comes with 11 different plastic materials and colors for your wide selection: from commodity plastics (ABS, PP, and others) to engineering plastics (HIPS, PA+GF30, and others). We also provide customization if required.

  • ABS (Black/ Grey/ Red/ Blue/ White)
  • ABS-PC (Black/ White)
  • PC (Black/ White/ Clear)
  • PMMA /Acrylic (Clear)
  • PP (Black)
  • HDPE (Black)
  • LDPE (Black)
  • HIPS (Black)
  • PBT (Black)
  • TPE (Black)
  • PA+GF30 (Black)

We designed our SPI finish card at a palm-size of 120×65×2 mm for easy carrying. You can bring it to any production site or even at a customer’s meeting. The card has two sides and comes with the 12 SPI finish grades from A1 to D3.

Here is the picture of Side A. From left to right:

SPI A1, SPI A2, SPI A3, SPI B1, SPI B2, and SPI B3 (Each plaque is at 40×20 mm.)

And here is the picture of Side B. From left to right:

SPI C1, SPI C2, SPI C3, SPI D1, SPI D2, and SPI D3 (Each plaque is at 40×20 mm.)

Check out our unboxing video below to learn more details:

Plastopia SPI Finish Cards are already trusted and widely used by brand companies like Apple, Samsung, Canon, Huawei, Foxconn, and many more.

Order Your SPI Finish Card Today