Is this a prototype of the smc Pentax-A☆ 600mm f/5.6 ED [IF]?: Pentax SLR Talk Forum: Digital Photography Review
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Pentax HD-D FA 150-450mm f4.5-5.6ED DC AW Super-Telephoto Lens for Pentax KAF Cameras : Amazon.in: Electronics
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SMC Pentax-A* 645 600mm F5.6 ED [IF] Reviews - 645 Telephoto Primes - Pentax Lens Reviews & Lens Database
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Sigma 745101 150-600mm f/5.0-6.3 for Canon EF Cameras 150-600mm Medium-Telephoto-Lens Fixed Zoom : SIGMA: Amazon.ca: Electronics
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