S Series: Symmetrical Threaded Inserts for Plastics

S Series Symmetrical Threaded InsertSay goodbye to expensive part orientation high-volume feeding mechanisms. Our symmetrical threaded inserts for plastic can be installed either end first for faster installation (using ultrasonic or thermal equipment) and lower costs.

By decreasing outward hoop stress, symmetrical threaded inserts decrease cycle times. Their proportionally engineered design ensures that the displaced material is encapsulated by knurls and undercuts. They are designed for straight hole applications and are ideal for thin-wall applications because little stress is applied to the walls of the part.

Recommended Hole Size – See chart below for installation hole size. Additional information can be found in our Design Guidelines.

Printable Catalog Page
Threaded Symmetrical Inserts Line Diagram
SYMMETRICAL THREADED INSERTS
INCH METRIC A
±.004		 B
±.004		 C
±.004		 Hole H
+.003 -.000		 Min.
Boss
Thread
Size		 Part
Number		 Thread
Size		 Part
Number
2-56 256X115S† M2.0 x 0.4 M20X115S† .123 .115 .138 .126 .252
256X157S M2.0 x 0.4 M20X157S .123 .157 .138 .126 .252
4-40 440X226S M2.5 x 0.45 M25X226S .154 .226 .175 .157 .314
M3.0 x 0.5 M30X226S .154 .226 .175 .157 .314
6-32 632X281S M3.5 x 0.6 M35X281S .185 .281 .206 .188 .376
8-32 832X321S M4.0 x 0.7 M40X321S .218 .321 .239 .221 .442
10-24 1024X375S M5.0 x 0.8 M50X375S .249 .375 .270 .252 .504
10-32 1032X375S .249 .375 .270 .252 .504
1/4-20 2520X500S M6.0 x 1.0 M60X500S .312 .500 .333 .315 .630
1/4-28 2528X500S† .312 .500 .333 .315 .630
5/16-18 3118X500S M8.0 x 1.25 M80X500S .374 .500 .393 .377 .754
5/16-24 3124X500S† .374 .500 .393 .377 .754
3/8-16 3816X500S† M10.0 x 1.5 M100X500S† .465 .500 .484 .468 .936
3/8-24 3824X500S† .465 .500 .484 .468 .936

† Non-Stocking Item – Minimum Order May Apply
Stainless Steel Symettrical Inserts – Class 3A/4H screw must pass with finger torque, standard class go gage may stop on last thread.
Part numbers for Stainless Steel Inserts are the same as listed in the chart, but ending with -SS.