Back Face Culling shader in Unity

Shader "Custom/backFaceChecker" {
Properties{
_Color("Main Color", Color) = (1,1,1,1)
_SpecColor("Specular Color", Color) = (0.5, 0.5, 0.5, 0)
_Shininess("Shininess", Range(0.01, 1)) = 0.078125
_MainTex("Base (RGB) TransGloss (A)", 2D) = "white" {}
_BumpMap("Normalmap", 2D) = "bump" {}
_Cutoff("Alpha cutoff", Range(0,1)) = 0.5
}

SubShader{
Cull Off
Tags{ "Queue" = "AlphaTest" "IgnoreProjector" = "True" "RenderType" = "TransparentCutout" }
LOD 400

CGPROGRAM
#pragma surface surf BlinnPhong alphatest:_Cutoff
#pragma exclude_renderers flash

sampler2D _MainTex;
sampler2D _BumpMap;
fixed4 _Color;
half _Shininess;

struct Input {
float2 uv_MainTex;
float2 uv_BumpMap;
};

void surf(Input IN, inout SurfaceOutput o) {
fixed4 tex = tex2D(_MainTex, IN.uv_MainTex);
o.Albedo = tex.rgb * _Color.rgb;
o.Gloss = tex.a;
o.Alpha = tex.a * _Color.a;
o.Specular = _Shininess;
o.Normal = UnpackNormal(tex2D(_BumpMap, IN.uv_BumpMap));
}
ENDCG
}

FallBack "Transparent/Cutout/VertexLit"
}