Can anyone tell me what this #IPTables entry related to #DNS is?

#Asus has "helpfully" added this to my parents' router.

Chain OUTPUT (policy ACCEPT)
target prot opt source destination
OUTPUT_DNS udp -- anywhere anywhere udp dpt:domain u32 "0x0>>0x16&0x3c@0x8>>0xf&0x1=0x0"
OUTPUT_DNS tcp -- anywhere anywhere tcp dpt:domain u32 "0x0>>0x16&0x3c@0xc>>0x1a&0x3c@0x8>>0xf&0x1=0x0"

#AskFedi