A study of the use of mechanical stretchers and its relation to knee morbidity in carpetlayers was conducted. The study was part of a health evaluation of carpetlayers' knee problems. Mechanical stretchers avoid the use of knee kickers which have been implicated as a major factor in knee injuries sustained by carpetlayers. The study group consisted of 132 male members of a carpetlayer's union, of which 94 had used a mechanical stretcher. They completed a questionnaire to assess their use of a mechanical stretcher and their subjective evaluation of the tool. The questionnaire responses were analyzed by a logistic regression technique. Thirty three percent of the subjects used the mechanical stretcher more frequently than the knee kicker, 20 percent used both tools about equally, and 47 percent used the knee kicker more often. Most of the subjects reported that the mechanical stretcher was easy to use, saved the knees, and was helpful in doing a better job quickly. Sixty percent of the subjects said the mechanical stretcher was difficult to carry around, 33 percent felt that it slowed down the job, and 39 percent that it was not always available at the job site. Availability and the ability to save the knees were significantly associated with use of the mechanical stretcher. Recommendations for increasing use of the mechanical stretcher were given. They include training carpetlayers to become proficient in using the mechanical stretcher, encouraging employers to provide an adequate number of mechanical stretchers for each work crew, developing light weight mechanical stretchers, and encouraging building contractors, carpet dealers, and unions to initiate or intensify educational programs that emphasize the health hazards of knee kickers.