I-PET strap (i-polyester strap) izindinganiso zokulawula ikhwalithi ziqinisekisa ukusebenza okungaguquki nokuphepha komthwalo. Ngokusho kokucaciswa kwe-ASTM D3950, ukuhlolwa kwekhwalithi kufanele kuqinisekise amandla aqinile, ubude, ukunemba kobukhulu, namandla ophawu lokushisa. Lo mhlahlandlela uchaza izindinganiso ezibalulekile zokulawula ikhwalithi, izimiso zokuhlola, nokuthi yini abathengi okufanele bayibheke lapho beqinisekisa ikhwalithi yebhande le-PET.