A sports mask for adjusting inhalation resistance settings to a user, the sports mask comprising; a head assembly configured to hold the sports mask to head of a user while the sports mask is in use; a face assembly to cover a mouth and nose region of the user, the face assembly comprising an outer unit, the outer unit being an individual standalone module, an inner most unit, the inner most unit being an individual standalone module separate from the outer unit, and a middle unit, the middle unit being an individual standalone module separate from the outer unit and the inner most unit, wherein the middle unit is received between the outer unit and the inner most unit to be assembled together to obtain the face assembly, each of the outer unit, the middle unit and the inner most unit having a cavity (10462,10442,10422) adapted to be located concentrically as the outer unit, the middle unit and the inner most unit being assembled together, wherein the outer, middle and inner most units are in decreasing order of sizes thereof and complements each other in shape to be snugly assembled together; a strap assembly (10464a, 10464b) extending from the outer unit of the face assembly and coupled to the head assembly to hold the face assembly to cover the mouth and nose region of the user; a grill cover coupled to the outer unit, the grill cover having an opening, wherein the opening is located concentrically to the cavities (10462, 10442,10422); a grill adapted to be received by the opening of the grill cover; and a modular air flow valve assembly adapted to be received by the cavity of the inner most unit to enable the air flow valve assembly to be in communication with the grill, the modular air flow valve assembly comprising, an airflow vent, the airflow vent having; a first cutout, and a second cutout configured below the first cutout and extending only up to half a portion of the first cutout, each of the first and second cutouts having air holes, an airflow valve adapted to be disposed over the first cutout of the airflow vent, the first cutout including a valve catcher engaged with the airflow valve, a slider unit adapted to engage with the valve catcher along the air holes, characterized in that: the airflow vent along the air holes includes a pair of valve catcher notches configured linearly across each other to engage with the valve catcher, and in that the valve catcher is adapted be placed over the airflow valve and distal ends of the valve catcher are engaged with the pair of valve catcher notches to place the airflow valve in the engaging position with the airflow vent, and, further the slider unit that is engaged with the valve catcher along the first cutout and adapted to extend up to an entire region of the second cutout to cover the air holes of the second cutout, the slider unit being slideable linearly over the valve catcher to open and close the air holes of the second cutout, the slider unit being adapted to be shifted linearly along the valve catcher to define multiple positions for generating various intermediate levels between a minimum and a maximum opening levels of the second cutout to vary flow of air flowing in the air flow valve assembly from the air holes of the second cutout. an outer unit, the outer unit being an individual standalone module, an inner most unit, the inner most unit being an individual standalone module separate from the outer unit, and a middle unit, the middle unit being an individual standalone module separate from the outer unit and the inner most unit, wherein the middle unit is received between the outer unit and the inner most unit to be assembled together to obtain the face assembly, each of the outer unit, the middle unit and the inner most unit having a cavity (10462,10442,10422) adapted to be located concentrically as the outer unit, the middle unit and the inner most unit being assembled together, wherein the outer, middle and inner most units are in decreasing order of sizes thereof and complements each other in shape to be snugly assembled together; an airflow vent, the airflow vent having; a first cutout, and a second cutout configured below the first cutout and extending only up to half a portion of the first cutout, each of the first and second cutouts having air holes, an airflow valve adapted to be disposed over the first cutout of the airflow vent, the first cutout including a valve catcher engaged with the airflow valve, a slider unit adapted to engage with the valve catcher along the air holes,