diff --git a/crt/shaders/slotmask.slang b/crt/shaders/slotmask.slang
new file mode 100644
index 0000000..c8a743b
--- /dev/null
+++ b/crt/shaders/slotmask.slang
@@ -0,0 +1,125 @@
+#version 450
+
+/*
+   OSSC Slot Mask simulator
+   by DariusG @2023
+
+*/
+
+layout(push_constant) uniform Push
+{
+ float MASK_INTENSITY;
+ float InputGamma;
+ float OutputGamma;
+ float THRESH,size, msk_scale;
+} params;
+
+// Parameter lines go here:
+
+#pragma parameter msk_scale "Mask Scale, to be equal to OSSC LINES" 4.0 4.0 5.0 1.0
+#define msk_scale params.msk_scale
+
+#pragma parameter MASK_INTENSITY "Mask Brightness" 0.2 0.0 1.0 0.05
+#define MASK_INTENSITY params.MASK_INTENSITY
+
+#pragma parameter size "Mask Size" 1.0 1.0 8.0 1.0
+#define size params.size
+
+#pragma parameter THRESH "Mask Threshold" 0.3 0.0 1.0 0.05
+#define THRESH params.THRESH
+
+
+layout(std140, set = 0, binding = 0) uniform UBO
+{
+	mat4 MVP;
+	vec4 SourceSize;
+	vec4 OriginalSize;
+	vec4 OutputSize;
+	uint FrameCount;
+} global;
+
+#define SourceSize global.SourceSize
+
+
+#pragma stage vertex
+layout(location = 0) in vec4 Position;
+layout(location = 1) in vec2 TexCoord;
+layout(location = 0) out vec2 vTexCoord;
+layout(location = 1) out vec2 ps;
+
+void main()
+{
+   gl_Position = global.MVP * Position;
+   vTexCoord.xy = TexCoord.xy;
+}
+
+#pragma stage fragment
+layout(location = 0) in vec2 vTexCoord;
+layout(location = 1) in vec2 ps;
+layout(location = 0) out vec4 FragColor;
+layout(set = 0, binding = 1) uniform sampler2D Source;
+
+vec3 mask(vec2 pos, vec3 col)
+{
+    vec3 msk = vec3 (MASK_INTENSITY);
+    float x,y;
+    vec2 p = pos*global.OutputSize.xy;
+    p = (p/size);
+     
+
+if (msk_scale == 4.0)
+{
+     x = fract(p.x/6.0);
+     y = fract(p.y/4.0);
+    if (x < 0.5){     
+     if (x<1.0/6.0 && y > 1.0/4.0) msk.b = 1.0;
+     else if (x<2.0/6.0 && x>1.0/6.0 && y < 3.0/4.0 ) msk.g = 1.0;
+     else if (x<3.0/6.0 && x>2.0/6.0 && y > 1.0/4.0 ) msk.r = 1.0;
+    }
+
+ else if (x > 0.4999){     
+     if (x<4.0/6.0 && y < 3.0/4.0) msk.b = 1.0;
+     else if (x<5.0/6.0 && x>4.0/6.0 && y > 1.0/4.0 ) msk.g = 1.0;
+     else if (x<6.0/6.0 && x>5.0/6.0 && y < 3.0/4.0 ) msk.r = 1.0;
+    }
+}
+
+if (msk_scale == 5.0)
+{
+     x = fract(p.x/6.0);
+     y = fract(p.y/5.0);
+    if (x < 0.5){     
+     if (x<1.0/6.0 && y > 1.0/5.0) msk.b = 1.0;
+     else if (x<2.0/6.0 && x>1.0/6.0 && y < 4.0/5.0 ) msk.g = 1.0;
+     else if (x<3.0/6.0 && x>2.0/6.0 && y > 1.0/5.0 ) msk.r = 1.0;
+    }
+
+ else if (x > 0.4999){     
+     if (x<4.0/6.0 && y < 2.0/5.0 || x<4.0/6.0 && y >= 3.0/5.0) msk.b = 1.0;
+     else if (x<5.0/6.0 && x>4.0/6.0 && y < 3.0/5.0 || x<5.0/6.0 && x>4.0/6.0 &&  y >= 4.0/5.0 ) msk.g = 1.0;
+     else if (x<6.0/6.0 && x>5.0/6.0 && y < 2.0/5.0 || x<6.0/6.0 && x>5.0/6.0 && y >= 3.0/5.0 ) msk.r = 1.0;
+    }
+}
+
+    col *= msk;
+    
+    return col;
+}
+
+void main()
+{
+    vec2 OGL2Pos = vTexCoord*SourceSize.xy;    
+    float cent = floor(OGL2Pos.y)+0.5;
+    float ycoord = cent*SourceSize.w; 
+    ycoord  = mix(vTexCoord.y, ycoord,0.7);
+    
+    vec3 col = texture(Source,vec2(vTexCoord.x,ycoord)).rgb;  
+    float l = dot(col,vec3(0.22,0.70,0.08));
+
+    col = col*col;
+    col = mix(mask(vTexCoord,col), col,l*THRESH);
+    col = sqrt(col);
+    
+    col *= mix(1.0,1.3,l);  //brightboost
+    FragColor = vec4(col, 1.0);
+} 
diff --git a/scanlines/ossc_slot.slangp b/scanlines/ossc_slot.slangp
new file mode 100644
index 0000000..612661f
--- /dev/null
+++ b/scanlines/ossc_slot.slangp
@@ -0,0 +1,23 @@
+shaders = "3"
+feedback_pass = "0"
+shader0 = "../misc/shaders/image-adjustment.slang"
+filter_linear2 = "false"
+scale_type_x0 = "source"
+scale_x0 = "1.000000"
+scale_type_y0 = "source"
+scale_y0 = "1.000000"
+shader1 = "../scanlines/shaders/ossc.slang"
+filter_linear2 = "false"
+scale_type_x1 = "viewport"
+scale_x1 = "1.000000"
+scale_type_y1 = "viewport"
+scale_y1 = "1.000000"
+shader2 = "../crt/shaders/slotmask.slang"
+filter_linear2 = "true"
+ia_saturation = "1.300000"
+ia_black_level = "0.060000"
+ia_bright_boost = "0.100000"
+L1 = "0.500000"
+L4 = "0.500000"
+L5 = "0.600000"
+HYBRID = "0.250000"