STI Series

Plastic Pipe Plugs for Product Protection, Tubing Inserts
STI Series
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Square Tubing Inserts

Square tubing inserts, otherwise known as STI Series products, are finishing plugs that companies can use in a variety of square applications. These durable plastic plugs for square tubing provide a clean, protective finish and simplify assembly for manufacturers. External tapered ribs ensure a secure fit in a wide range of tubing gauges, and a sleek outer appearance ensures a flawless seam when installed.

They also resist vibration and maintain retention under load, reducing onsite maintenance. With square tubing plugs, you can spruce up the style of older furniture pieces, complete unfinished installation work, and keep unsightly interior components hidden from view.

Installers appreciate quick press-fit installation that saves time on production lines. The plugs seal openings to block dirt and moisture, extending service life. For added functionality, our threaded inserts for square tubing accept fasteners and allow secure attachments.

Learn more about our versatile STI Series products below.

  • Color: Black
  • Material: Low Density Polyethylene
  • LDPE service temperature: 150°F (66°C)
  • Some parts are also available with domed and/or other types of top profiles
  • Additional sizes available (consult factory for details)
  • RoHS Compliant
STI Series product diagram

Product Options

Please confirm that your Part Number is correct and adjust the other selections below to meet your application's requirements.

Make Your Selection Below

PART NO. COLOR TO FIT
TUBE SIZE		 TO FIT
TUBE GAUGE		 TUBE WALL
THICKNESS		 PRODUCT OPTIONS
STI-2-1/2 14-20 Black 2 1/2" 14-20 .083-.035 Carton 300 1 100 10 208.50 262.27 91.79 0
STI-3.63 7-11 3.63" 7-11 .179-.120 Carton 75 1 50 10 126.83 279.17 195.42 0
STI-1/2 16-18 Black 1/2" 16-18 .065 -.049 Carton 10,000 1 1,000 100 533.00 119.70 65.24 1,255
STI-5/8 14-20 Black 5/8" 14-20 .083-.035 Carton 5,000 1 1,000 100 266.50 119.70 65.24 1,256
STI-3/4 14-20 Black 3/4" 14-20 .083-.035 Carton 5,000 1 1,000 100 308.50 193.80 67.84 1,257
STI-7/8 14-20 Black 7/8" 14-20 .083-.035 Carton 3,000 1 1,000 100 237.90 188.49 65.92 1,258
STI-1 10-14 Black 1" 10-14 .134-.083 Carton 2,500 1 1,000 100 200.75 252.80 88.52 1,259
STI-1 14-20 Black 1" 14-20 .083-.035 Carton 2,500 1 1,000 100 200.75 252.80 88.52 1,260
STI-1-1/8 14-20 Black 1 1/8" 14-20 .083-.035 Carton 2,000 1 500 50 273.00 214.50 75.08 1,261
STI-1-1/4 10-14 Black 1 1/4" 10-14 .134-.083 Carton 1,600 1 500 50 223.36 219.65 76.87 1,262
STI-1-1/4 14-20 Black 1 1/4" 14-20 .083-.035 Carton 1,600 1 500 50 223.36 219.65 76.87 1,263
STI-1-3/8 14-20 Black 1 3/8" 14-20 .083-.035 Carton 1,000 1 500 50 412.72 463.40 162.20 1,264
STI-1-1/2 10-14 Black 1 1/2" 10-14 .134-.083 Carton 1,000 1 500 50 230.10 362.05 126.71 1,265
STI-1-1/2 14-20 Black 1 1/2" 14-20 .083-.035 Carton 1,000 1 500 50 230.10 362.05 126.71 1,266
STI-40 MM 14-20 Black 40 mm 14-20 2.0 -1.0 mm Carton 1,000 1 500 50 272.95 285.16 99.80 1,267
STI-1-3/4 10-14 Black 1 3/4" 10-14 .134-.083 Carton 500 1 250 25 156.60 218.09 86.18 1,268
STI-50 MM 11-20 Black 50 mm 11-20 3.2-1.0 mm Carton 500 1 250 25 382.13 561.30 196.45 1,269
STI-2 10-14 Black 2" 10-14 .134-.083 Carton 500 1 250 25 168.80 281.38 98.48 1,270
STI-2 14-20 Black 2" 14-20 .083-.035 Carton 500 1 250 25 178.95 281.38 98.48 1,271
STI-2-3/8 6-10 Black 2 3/8" 6-10 .203-.134 Carton 250 1 100 10 204.72 238.22 83.38 1,272
STI-60 MM 6-11 Black 60 mm 6-11 5.0-3.0 mm Carton 250 1 100 10 204.71 230.76 80.76 1,273
STI-2-1/2 10-14 Black 2 1/2" 10-14 .134-.083 Carton 300 1 100 10 208.50 262.27 91.79 1,274
STI-3 10-14 Black 3" 10-14 .134-.083 Carton 200 1 50 10 224.44 176.44 123.51 1,275
STI-80 MM 5-13 Black 80 mm 5-13 2.5-5.6 mm Carton 125 1 50 5 208.80 275.15 96.52 1,276
STI-3-1/2 6-11 Black 3 1/2" 6-11 .194-.120 Carton 100 1 25 5 212.95 167.42 117.19 1,277
STI-4 7-11 Black 4" 7-11 .179-.120 Carton 108 1 60 5 230.76 403.16 117.59 1,278
STI-5 7-11 Black 5" 7-11 .179-.120 Carton 60 1 25 5 147.57 193.35 143.46 1,279
STI-6 7-11 Black 6" 7-11 .179-.120 Carton 48 1 12 5 243.48 191.42 279.15 1,280

More Options

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