820542511 is a 390V typical varistor from Würth Elektronik in a Disc 14mm through-hole package. It handles 4.5kA surge current and 120J energy absorption.
Metal Oxide Varistor (MOV) with 510V typical varistor voltage, 320VAC/410VDC maximum, 7.5kA peak surge current, and 382J surge energy in a Disc 14mm through-hole package.
Kyocera AVX VE24P01750K is a 270V typical varistor (243V min, 297V max) rated for 10kA peak surge current and 190J energy absorption in a 24mm disc through-hole package.
