Inikeza indawo yokugcina ama-dumbbell okuqeqesha isisindo samahhala ekuqeqesheni okuphambanayo, isikhala se-2-Tier samapheya angu-10 wama-dumbbell angu-20 anesisindo esijwayelekile, nesikhala esengeziwe phezulu sivumela ukugcinwa kwezinsiza ezisizayo njengamabhola okuqina, amabhola emithi, njll. Ngenxa ye-DHZ's uchungechunge olunamandla lokuhlinzeka nokukhiqiza, uhlaka lwesakhiwo semishini siqinile futhi sinewaranti yeminyaka emihlanu.