SSR Metals Pvt. Ltd. Offers SSR SWD Induction Field Circuit. SSR Metals Pvt. Ltd. Is an ISO 9001: 2000 certified company. SSR SWD Induction Field Circuit falls under the category of `Scientific Equipment Enclosure`. It provides a short-wave frequency of 27.12 MHz that penetrates deep into muscle tissues with negligible heating in the fatty layer or bone.