Wannan injin yana da amfani ga mai sarrafa gilashin jaket don ƙarancin zafin jiki da yanayin sanyaya. An rufe duk hanyar hawan keke, tankin faɗaɗa da hawan keke adiabatic ne, haɗin injin ne kawai. Komai zafin jiki yana da girma ko ƙasa, ana iya canza injin ɗin kai tsaye zuwa yanayin sanyi da sanyaya idan yana ƙarƙashin yanayin zafi mai girma.