Nova NHC 3921 one of the worst trimmer ever .It is my personal experience about nova NHC trimmer I was purchase just 2 week again from galaxy mall .in 300rs .It quality is really bad because the blade made of bad quality of steed therefor it increases the change to get stain .The moter is also too bad quality it is not able to trime the hair complatity .The battery backup of really too worst because it never last more than 10 min after charging 4to 5 hour .It make too noice and some time it stop working then I have to shake then it again startThe charging wife is too short I have to hang the trimmer on wall because to short wife and many time it fall down due to that wireQuality of the plastic and wire is too poor because only after 1 week by mistake trimmer slip from my hand and it crack from the corner .It trimmer experience is not good it not able to trime. the hair.completly it leave the hair some places .The shap of the trimmer is not confortable it is very difficult to handle the trimmer due to its shape and size