49mm To 77mm Macro Reverse Adapter Ring For Pentax K Pk K-1ii Kp K-70 K-1 K-3ii K-s2 K-s1 K-5iis K-5ii K-5 K-3 K-r K-x K-m K-7 K - Lens Adapter - AliExpress
Urth Pentax K to Sony E Lens Mount Adapter | Urth AU
Amazon.com : Fotodiox DLX Stretch Lens Mount Adapter - Pentax K Mount (PK) SLR Lens to Fuji X-Series Mirrorless Camera Body with Macro Focusing Helicoid and Magnetic Drop-in Filters : Electronics
Fotodiox 10-LA-MR-PK-49 49MM Filter Thread Macro Reverse Mount Adapter Ring for Pentax K Camera Fits Pentax : Amazon.ca: Electronics
Canon-m42 Macro Adapter Ring For Canon Eos Ef Lens To M42 Screw Mount Zeiss Pentax Mamiya Camera - Lens Adapter - AliExpress