Hahaemall Sliding Barn Door Hardware Material: High purity bearing Gcr15 Steel , Steel thickness:0.24'' , Surface: Black frosted, corrosion protection. Reference: Door capacity;150lb-230lb, Door panel width;40"-48"; Door panel thickness: 1 3/8"-1 3/4".The rail hole-space is pre-drill 16'' US standard distance layout. Design: Rubber covered Stopper, Noise reduction. POM floor guide, Keep the door in balance. Screws: 8.8 grade, High bearing capacity. 8FT Package Include: Roller(4) Stopper(4) Sliding track(4pc*4ft ) connector(12) Brackets(6)Anti-pad:(4) Floor guide(2) Installation manual(1); Hardware Only, DOOR NOT INCLUDED. Service : we provide customized service, 5 years warranty. 100% money back guarantee, 24 hours online customer service, any part missed or damage during shipping, please let us know, we will send replacement at no charge at first time.