Thenunin faifai shi ne kayan aikin da ya dace tsakanin drowa da majalisar, kuma shi ne bangaren da ke dauke da nauyin aljihun. Bisa ga kayan, ana iya raba shizamewar baƙin ƙarfe dogokumabakin karfedogo nunin dogo. Dangane da aikin, an raba shi zuwa faifai na yau da kullun, nunin faifai, nunin faifai, rebound, famfo doki, nunin faifai mai nauyi, da dai sauransu. Titin dogo yana da sassa uku (cikakken tsawo) da sassa biyu ( nunin 3/4). Dangane da bukatun abokin ciniki,Tsawon zai iya zama 150-2000MM, kuma nauyin zai iya zama 10KG-200KG.. Dangane da tsarin samarwa, ana iya raba shi zuwa nunin faifan foda, nunin faifan ƙwallon ƙarfe, faifan ɓoye, bugun dawakai, da faifan kwando. Ƙarfin ɗaukar nauyi na dogo na nunin faifai yana da alaƙa da kauri daga cikin kayan, mafi girman kayan, mafi girman ƙarfin ɗaukar nauyi. A nisa na karfe ball slide dogo za a iya yi daga 17mm zuwa 76mm, da dai sauransu, da launi za a iya galvanized da baki. Za a iya yin titin dogo mai fesa foda a launuka da yawa, wanda aka ƙaddara gaba ɗaya ta launin foda na filastik.