Hauv xov xov kev sib txhuam, kev npaj ntawm cov fibers yog qhov cuam tshuam. Tus naj npawb ntawm cov xov paj tso rau hauv conical muab kauv thiab cov cylindrical kauv yog qhov tsawg dua li ntawd hauv cov xov paj rotor, kev suav tsuas yog 12%. Cov ntawv sib txuam thiab cov xov cev sib faib ua rau 40%, thiab qhov seem feem ntau yog cov sib tsoo thiab ib nrab ntswj kab.
