With this tool you could do many great exercises. Do This Yoga Bungee Cord Resistance Belt Set Include Ceiling Mount?. DIFFERENT BUNGEE CORD CONSIST OF DIFFERENT ELASTIC CORES(The thickness of the elastic cores is different):For weight class-1, 50kg,consists of 3 thin elastic cores (Φ12mm),For weight class-2, 60kg,consists of 3 thin cores ( Φ13mm), For weight class-3, 70kg,consist of 2 thin elastic core and 1 thick cores (Φ13mm and Φ15mm),For weight class-4, 80kg,consists of 1 thin elastic core and 2 thick cores (Φ13mm and Φ15mm),For weight class-5, 90kg, consists of 3 thick cores(Φ15mm).
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