Bestar yana samarda cikakkun layin ƙofa da kayan haɗi. Wannan ya hada da duk kayan aikin kofa da kayan kwalliya kamar maɓuɓɓugar torsion, dam ɗin bazara, ƙwanƙwasa, sarkar hawa, sakata, kullewa ta tsakiya, ƙwace yanayin, stapler, fil, shaft tube…