trailer manual slack adjuster 1good shell strength 2good modulus of elasicity 3durable ... have a high visibility.Trailer Manual Slack Brake Adjuster1.spline teeth 10(still can produce of 8,10,14,28,37)2.holes 2 ... (still we can produce holes of 1,2,3,4)3.net weight:2 ... :40 below 0 to 80 degree centigrade.8.10teeth,28teeth manual slack adjuster KN47011