TANDEM plus BLUMOTION brings together all of the features, innovations and benefits that Blum has developed since first manufacturing drawer runners in the early 1960s. The first time you open and close a fully loaded drawer, you will quickly realize that TANDEM plus BLUMOTION concealed runners are unmatched in quality, style and running action.?The availability of a wide variety of locking devices, rear mounting brackets, sockets, and templates make installation virtually effortless.?Drawers close softly and effortlessly with soft-close BLUMOTION. Four-dimensional adjustment Elongated holes for depth adjustment Bottom mount holes on 15", 18" and 21" 100 lb static load capacity Full extension concealed runners Face frame or frameless cabinets BLUMOTION soft closing TANDEM smooth running action vailable in 9" to 21" lengths 13mm (1/2") to 16mm (5/8") drawer thickness Made in the USA