Temperature limiter for some Parmco ovens. Rated 170 degrees, this is the device that cuts the power to the elements if the oven cavity overheats. 
Temperature Limiters Explained
PARMCO: FS600BC, FS600BG, FS600SC, FS600SG, FS60WP4, FS900BG, FS900SC, FS900SG, OV145B7, OX7-4-6B-8-1, PPOV-6S-PYRO-2, OX7-6-6S-5-1, OX7-3-6S-5-1, OX7-2-6S-5-1, PPOV-6S-SIDE, PPOV-6S-SIDE-1, OX7-3-6S-8-1, OX7-2-6S-8-1, OX7-6-6S-8-1,
PPOV-6S-DT-4, OX7-4-6W-5-1, OX7-4-6W-8-1, VERSO3-1, VERSO3-2, VERSO1-1,
VERSO1-2, PPOV-6S-DT-3, OX7-4-6B-8, PPOV-6S-SIDE, OX7-3-6S-5, OX7-2-6S-5,
OX7-5-6S-5, OX7-2-6S-8, OX7-5-6S-8, OX7-3-6S-8, OX7-4-6W-8, OX7-4-6W-5, FX60CER, FS600WG, OX-1-6S-5, OX-1-6S-8, FX60H, OX7-4-6S-5, VERSO X5-F, VERSO X9-F
EUROTECH: ED-EUROC90BK, ED-EUROC90SS, ED-BIO5FMTBK, ED-BIO5FMTSS, ED-BIO11FTBK, ED-BIO11FTSS, ED-BIO5FMTBK, ED-BIO5FMTBK.2, ED-BIO5FMTSS, ED-BIO8FDTBK, ED-BIO8FDTSS, ED-BIO11FTBK, ED-BIO11FTSS, ED-BIO11FTBK.2, ED-BIO11FTSS.2
VOGUE: 310105, 310106, 310152, 310153
HAIER: