local aWeapons =
{
    25, 26 -- Edit this
};

addEventHandler ( 'onClientPlayerDamage', root,
    function( pAttacker, iWeaponID )
        if pAttacker and pAttacker ~= localPlayer then
            for i, v in ipairs( aWeapons ) do
                if v == iWeaponID then
                    setElementVelocity ( localPlayer, 0, 0, 0 );
                end
            end
        end
    end
);