Ultrasonic/Heat Staking Inserts

SI (Standard Inserts) Ultrasonic/Heat Staking Inserts are hexagonal-shaped body inserts that provide rotational torque resistance and knurling provides torque out resistance. The heat staking inserts are installed by pressing the insert into the mounting hole with a thermal press to melt the plastic surrounding the insert. The SI® brand inserts employ press-in and heat/ultrasonic installation methods to provide strong, reusable, and permanent threads in plastic. These SI® inserts are available in brass, stainless steel, and aluminum. The applications include wearables, smartphones, handheld devices, automotive, aerospace and defense, medical, transportation, industrial, and recreational equipment.

Results: 268
Select Image Part # Mfr. Description Datasheet Availability Pricing (USD) Filter the results in the table by unit price based on your quantity. Qty. RoHS ECAD Model Product Type Material Mounting Hole Size Length Outside Diameter Thread Size Packaging
SI Mounting Hardware ULTRASONIC INSERT, BRASS 187,278In Stock
12,674On Order
$0.26
$0.178
$0.143
$0.134
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 3.58 mm 5.56 mm 4.37 mm M3
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 92,438In Stock
16,125On Order
$0.52
$0.371
$0.297
$0.267
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 3.58 mm 5.56 mm 4.37 mm M3
SI Mounting Hardware HI-TORQUE INSERT, BRASS 3.43X3.86 M3 THREAD ULTRASONIC HEAT STAKING DIAGONAL 14,444In Stock
$0.41
$0.291
$0.233
$0.209
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 4.01 mm 3.43 mm M3
SI Mounting Hardware HI-TORQUE INSERT, BRASS 3.18X3.07 M2 THREAD ULTRASONIC HEAT STAKING DIAGONAL 9,561In Stock
$0.47
$0.333
$0.267
$0.24
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 3.23 mm 3.18 mm M2
SI Mounting Hardware HI-TORQUE INSERT, STAINLESS 3,764In Stock
$1.21
$0.898
$0.707
$0.60
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 0.316 in 0.5 in 0.342 in 1/4-20
SI Mounting Hardware HI-TORQUE INSERT, STAINLESS STEEL 3.43X3.86 M3 THREAD ULTRASONIC HEAT STAKING DIAGONAL 8,486In Stock
$0.81
$0.575
$0.461
$0.434
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 4.01 mm 3.43 mm 4.55 mm M3
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 6,783In Stock
$0.66
$0.464
$0.372
$0.335
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 0.185 in 0.25 in 0.219 in 6-32
SI Mounting Hardware HI-TORQUE INSERT, BRASS 59,989In Stock
$0.37
$0.263
$0.21
$0.189
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 4.01 mm 5.74 mm 4.55 mm M3
SI Mounting Hardware HI-TORQUE INSERT, STAINLESS 8,105In Stock
$0.79
$0.555
$0.445
$0.419
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 0.189 in 0.281 in 0.21 in 6-32
SI Mounting Hardware HI-TORQUE INSERT, STAINLESS STEEL 3.18X3.07 M2 THREAD ULTRASONIC HEAT STAKING DIAGONAL 9,923In Stock
$0.54
$0.381
$0.305
$0.274
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 3.23 mm 3.18 mm 3.73 mm M2
SI Mounting Hardware HI-TORQUE INSERT, BRASS 5.72X6.27 M5 THREAD ULTRASONIC HEAT STAKING DIAGONAL 10,311In Stock
$0.56
$0.397
$0.318
$0.286
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 6.43 mm 5.72 mm M5
SI Mounting Hardware HI-TORQUE INSERT, STAINLESS 10,312In Stock
$0.86
$0.61
$0.489
$0.44
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 4.01 mm 5.74 mm 4.55 mm M2.5
SI Mounting Hardware ULTRASONIC INSERT, BRASS 9,560In Stock
$0.64
$0.453
$0.363
$0.327
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 6.25 mm 9.53 mm 7.54 mm M5
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 10,229In Stock
$0.70
$0.492
$0.394
$0.355
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 3.89 mm 3.43 mm 4.37 mm M2.5
SI Mounting Hardware HI-TORQUE INSERT, BRASS 13,080In Stock
$0.37
$0.26
$0.208
$0.196
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 0.223 in 0.321 in 0.243 in 8-32
SI Mounting Hardware HI-TORQUE INSERT, STAINLESS 9,053In Stock
$1.32
$0.978
$0.762
$0.718
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 8.03 mm 12.7 mm 8.69 mm M6
SI Mounting Hardware HI-TORQUE INSERT, BRASS 9,727In Stock
$0.94
$0.662
$0.53
$0.478
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 6.43 mm 9.53 mm 7.92 mm M5
SI Mounting Hardware HI-TORQUE INSERT, BRASS 20,327In Stock
16,000Expected 2/24/2027
$0.44
$0.313
$0.25
$0.236
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 4.01 mm 5.74 mm 5.54 mm M3
SI Mounting Hardware HI-TORQUE INSERT, BRASS 12,138In Stock
$0.51
$0.363
$0.29
$0.261
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 5.67 mm 8.15 mm 6.17 mm M4
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 8,745In Stock
$0.53
$0.373
$0.298
$0.281
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 0.141 in 0.219 in 0.172 in 4-40
SI Mounting Hardware HI-TORQUE INSERT, STAINLESS 4,695In Stock
10,000Expected 3/5/2027
$1.06
$0.793
$0.617
$0.582
Min.: 1
Mult.: 1
Inserts Threaded Insert Stainless Steel 5.67 mm 8.15 mm 6.17 mm M4
SI Mounting Hardware HI-TORQUE INSERT, BRASS 26,933In Stock
11,000Expected 11/10/2026
$0.60
$0.429
$0.343
$0.309
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 5.67 mm 8.15 mm 7.14 mm M4


SI Mounting Hardware ULTRASONIC INSERT, BRASS 20,594In Stock
52,000On Order
$0.22
$0.159
$0.127
$0.115
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 3.89 mm 3.43 mm 4.37 mm M3
SI Mounting Hardware HI-TORQUE INSERT, BRASS 14,546In Stock
10,000Expected 4/12/2027
$0.46
$0.332
$0.266
$0.239
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 3.23 mm 4 mm 3.73 mm M2
SI Mounting Hardware HI-TORQUE INSERT, BRASS 5,503In Stock
16,427On Order
$0.79
$0.588
$0.484
$0.41
Min.: 1
Mult.: 1
Inserts Threaded Insert Brass 8.03 mm 12.7 mm 9.53 mm M6 Bulk