 So, let us see we will move to the next stage, then Avinash luckily went and joined a company in Delhi which is a solar based company, they work on making instruments for companies and schools and you know to make solar education. So, then I said Avinash use the plastic bottle, let me go to the best manufacturers in the country to make glass shells, so we went to them and we said we want a double world vacuum flask. At that time we did not even know that we need to mention those thicknesses, thicknesses are very critical in this because if I have more thickness my you know the heat transmittivity losses are much larger. We got this glass and we conceived this window mounted solar oven, we founded a lot of issues then I called up Avinash, Avinash what is this you are working in a solar company, please help us not working and I worked very hard it took 8 months to manufacture this glass jars, vacuumize them, build all the CAD models to make the prototype and it is not working. So, he came back and then he said sir you have a lot of heat in Bombay, I will go to my hometown Orangabad and I will show you what happens, so he took this glass jar in the bus to Orangabad and he baked cake in that and it is working. So, now the issue is that we need to understand the various important engineering aspects in this, what are the issues of thermal engineering in this, what are the issues of solar you know conduction and convection issues in this and it is really really very very high you know technology and understanding which need to go in. So, now what all did we learn from this case, we clearly learnt that there is a very serious issue about the glass wall thickness absorbing most of the heat in Bombay whereas when you went to Orangabad the temperatures are so high that he could cook very easily, the black body absorbs the heat efficiently that was very clear. So, if my container inside is reflected like if I put a stainless steel container inside will it cook? It is not rocket science people say that you have matte black vessels inside it will absorb all the heat, so it is basic science more the black surface more the heat maximum heat is transferred through conduction process food containers need to be exposed to the sun directly, so these are the insides we got. So, went back again to the conception first idea, let us check let us make polycarbonate boxes, so these are two wall polycarbonate boxes. So, we have to always design in the difficult circumstances rather than design for best circumstances, if you design for difficult circumstances you will get very good design. Avinash put this reflector surface on the door he made this double walled fish tank design one in glass because fish tank manufacturers are there they quickly may give us in glass and we made one in polycarbonate we tested both of them and we have put our whole setup on the terrace to check to temperatures to measure we found out that the polycarbonate one was much better because the losses with conduction were less in polycarbonate and we started using the you know tiffin boxes which came from the box type solar ovens which are well in the market. And to a surprise the tiffin boxes were very thin made up of aluminum and painted black matte outside, so we copied the design we took the same boxes and they started working well we started making dal chawal and then we measure the temperature to a shock it was 108 degrees this was a great sort of leap for us and then from here you know we start cooking rice regularly we said that if you have a product you need to experience it yourself first. So, we start cooking every day in these oven before lunch and sometimes you would eat kachcha chawal where there is no sun but you know we said we have to feel the pain of anybody using a solar oven you know passionately.