Manfrotto 055 Magnesium Ball Head with RC4 Quick MH055M0-RC4 B&H
Manfrotto Manfrotto Distribution MAN-394 RC4 Low Profile Rectangular Rapid Connect Adapter with 410PL Plate- Black at Lowes.com
Manfrotto 490RC4 maxi ball with RC4 R.C.SYST. - Tripod Heads - Crown Camera | Product Specification
Bogen/Manfrotto 488RC4 Midi Ball Head with RC4 Quick Release at KEH Camera
Amazon.com : Haoge CP-64 Quick Release Clamp with RC4 / 400PL Base Adapter Convertor for Manfrotto RC4 System to Arca-Swiss Compatible, Fit 400PL / 405/410 / RC4 : Electronics
Converter Arca Quick Release Plate to Manfrotto RC4 405 Tripod Ball Head Clamp | eBay