There has been a lot of talk about lately about sealing harps with micropore, yet the talk seems to be mainly about sealing plastic body harps. I have never had a problem with a Special 20 or LO leaking but sealed one of my Special 20 harps anyway just to try it. It didn't make a noticable differance to me. My problem has always been leaky Marine Bands, yet I have not read anything on the Harp-L on sealing them. Does anyone know if the milipore attached to the comb works good on a MB. I am thinking of trying this along with screws and bending the read plates to apply more pressure down on the comb.