They include male condoms, female condoms, cervical caps, diaphragms, and contraceptive sponges with spermicide. Diaphragms and caps are often used in conjunction with spermicides. This results in seals, gaskets, diaphragms and other becoming defective quickly. Clotrimazole creams and suppositories contain oil which may weaken latex condoms and diaphragms. Various models were made, including ones with condenser diaphragms, ribbons, moving coils, and carbon buttons. Free-piston Stirling engines include those with liquid pistons and those with diaphragms as pistons. Some designs avoid sliding surfaces altogether by using diaphragms for sealed pistons. It has no venturi, no pressure chambers, no diaphragms, and no discharge valve. Using diaphragms eliminates friction and need for lubricants. Birds also do not have diaphragms or pleural cavities. Additionally, adolescents lack access to contraceptive methods like oral contraceptives and diaphragms. Common technologies use metal, ceramic, and silicon diaphragms. Rubber diaphragms will eventually leak and need to be replaced. Ceramic and metallic diaphragms are used. Cervical barriers such as diaphragms may offer some protection against these infections.