RAINBOW | O RING | R172451
Part For TOP LOAD IN-LINE SPA CARTRIDGE MODELS RTL AND RCF OPTIMUS #4670-E VARIOUS MFG NUMBERS INSIDE DIAMETER: 15/16" OUTSIDE DIAMETER: 1-3/16" CORD THICKNESS: 1/8" 
A&A MANUFACTURING
A&A LeafVac O-Ring for the Lid to the Canister Part# 523979 LeafVac O-Ring Product Info
Generic
APCO2162 | O-Ring, Generic 354053 PACFAB TANK O-RING O336 HAYWARD SPX0714L JACUZZI 47035803R MARTEC / SONFARREL 201004 PENTAIR / PACFAB 354053 STARITE / SWIMQUIP 355051438 355051409 WMC JS1903
Pentair/Rainbow
PENTAIR/RAINBOW | GASKET, BAKER HYDRO RING | R36046
Generic
64918 Generic O-Ring, O-184 90-423-1184 O-184 O-Ring, O-184