There are two kinds you can choose A One arm without servosB One arm Two ServosFeature The Kit comes with hardware no assemblyClamp Max open is 55mmClamp total length 108mmClamp total width 98mm when the Clamp open Working voltage 4 8 6V when the Clamp open The plank kit is very lightCompatible with HS322 HS422 MG995 SG5010 servo Specification Name 2 DOF Aluminum Robot Arm ClampDOF 2Paw material aluminum alloyPaw weight about 68g without motor Paw maximum opening angle 55mm without expansion board when the maximum opening angle spacing of 55mm the largest expansion board after the installation is 95mm Claws overall length 108mm overall maximum length when closed paw Claws overall width 98mm maximum overall width of the paw when open Package included 1 x Aluminum Clamp 2 DOF2 x MG996R Servo