Cerfificates & Approvals: Manufactured by quality assured ISO9001 factory since 2001 UL and CUL Listed No.R18696 100,000 cycles passed Warranty: PT100 Series door closer is guaranteed for 5 years from the date of manufacture against any defect in material or workmanship.Defective product will be replaced with a new unit.This guarantee is void if the product has been subject to misapplication or abuse. Construction & Technical Dtails Constructed with precise aluminum die-cast body with steel arm against rust Heat treated steel rack & pinion immersed in high grade oil operate a nest of coils to give a smooth precise action & minimum wear Piston and spindle been heat treated for high strength Stable hydraulic fluid for any climatic operation & constant lubrication from - 20 °C to +50 °C