LEGO LEGO Functions: Power Functions IR RX (8884) for sale online | eBay
Compatible With Lego 8884 Technology Mechanical Group Servo Motor Pf Accessories Dual Remote Control Receiver Lithium Battery - Blocks - AliExpress
LEGO - Genuine Power Functions - 8884 - Power Functions IR Receiver - Tested | eBay
Power Functions IR Remote Control & IR Receiver Set Compatible With Model 8879 8884 - BuildingToyStore.com
Power Functions IR RX 8884 - LEGO® Powered Up - Building Instructions - Customer Service - LEGO.com US
BrickLink - Part 58123bc01 : LEGO Electric Power Functions Receiver Unit with Dark Bluish Gray Bottom and Black V2 Print (Version 2) [Electric] - BrickLink Reference Catalog