The Ase Utra S series SL5i sound suppressors are available in various calibres, from .222 Rem up to 8 mm calibre. SL5i suppressors are updated and lightened variants of the earlier SL5 suppressor. Manufactured in Finland by Ase Utra Ltd, the S series SL5i suppressors are manufactured out of 300 series stainless steel and are assembled by welding. S series SL5i suppressors feature a robust construction and they are built for a long service life. The S series SL5i suppressor adds only 103 mm to the length of the weapon, the diameter being 44.5 mm. S series SL5 suppressors are available with a variety of internal threads to fit directly onto the rifle barrel. Standard threads include for example M14x1, M15x1, M17x1, M18x1, ½"x20 UNF and 5/8"x24 UNEF to fit most current centrefire rifles. Other threads are also available. The S series SL5i suppressors reduce the weapon sound pressure level by 22-30 dB (depending on calibre, ammuntion type, measurement location). The S series SL5i suppressors also reduce recoil and muzzle flash significantly. Rifles tested with the SL series suppressors, comply with the latest personal exposure limit set by the European Directive 2003/10/EC (140 Pa tai 137 dB (C)).