They include tapered, straight hole, and symmetrical inserts, as well as threaded studs. The inserts start at 0 to 80 for inch threads and M1.6 for metric. The tapered H Series is said to outperform competitive inserts in ultrasonic and thermal installation in thermoplastics and structural foams. The H Series eliminates outward stress during installation and features a "knuckle knurl" that promotes uniform material flow into diagonal knurls and undercuts. This, along with its tapered design, boosts holding strengths and cuts installation time.