Delta 1/2-in ID Compression x 1/2-in OD Compression Brass Diverter Valve in the Tub & Shower Valves department at Lowes.com
3-Way Shower Arm Diverter for Hand Shower in Polished Brass U4929-PB-PK | Delta Faucet
All Metal 3-Way Shower Arm Diverter with Holder For Dual Shower Heads – The Shower Head Store
3 Way Brass Shower Arm Adapter G1/2'' Shower Diverter Valve for Handheld Shower Head and Fixed Shower Head - AliExpress
Shower Arm Diverter Valve for Hand Shower and Fixed Spray Head, TSV G1/2" 3-Way T-adapter Connector, Brass Universal Bathroom Shower System Replacement Part, Water Flow Control, Chrome - Walmart.com