Amazon.com: Geekstory for ATMEL 51 AVR USB ISP ASP Microcontroller Programmer Downloader with Cable + 10Pin to 6Pin Adapter Board for Ender 3 or Ender 3 Pro : Electronics
Amazon.com: KeeYees 2pcs Downloader Programmer for USBASP for ISP with Cable and 10Pin to 6Pin Adapter Board for 51 for AVR Series Microcontroller : Electronics
Pololu USB AVR Programmer v2.1
Amazon.com: 2pcs 10 Pin Convert to Standard 6 Pin Adapter Board F ATMEL AVRISP USBASP STK500 CF : Electronics
AVRISP 10 to 6 Pin Adapter for MKII USBASP STK500 -