Check the listing for details. CERROPI Large Newtons Cradle Pendulum with 7 Balls, Physics Perpetual Motion .... Condition: New. Listed at 50.50 USD. CERROPI Large Newtons Cradle Pendulum with 7 Balls, Physics Perpetual Motion Desk Toys for Office, Calm Down Fidgets, 50+ Sec Swingtime (Beech Base) Description Features: SCIENTIFIC DESIGN-CERROPI newton's cradle adopt scientific design,keep the pendulum balls perfectly lined up,make it possible to swing 50s+. Perfect demonstration of the scientific law of momentum conservation and energy conservationSUPERIOR QUALITY-Our newtons cradle made of 8mm chromed metal steel bar, 20mm steel Ball,high-impact nylon, ultra-thin nano technology provide extremely durable oscillatory support, durable for long time use.Pursuit of craftsmanship spirit inspired us to continuously produce high-quality goodsWIDE APPLICATION-This newton balls can be used as office desk gadgets toys to relieve stress; as teaching aid,teaching science intuitively; as toys for family activities, to inspire your child's creativityEXQUISITE PACKEGING-We use individual wrapping paper to protect each ball and secure it in foam shockproof material,Perfect for Christmas gifts, Thanksgiving gifts, birthday gifts,Mother's Day gift,Father's Day gift,Valentine's Day gift etc.WARRANTY & NOTICE- 1 YEAR warranty, If any piece breaks we send replacement balls, strings and plug to you. Messages reply within 12 hours. NOTE: clean the ball thoroughly before using for the longer swing time,one extra ball and a silky soft cleaning cloth are included in the package Product Details: UPC: 715668926103Manufacturer: CERROPIGlobal Trade Identification Number: 03Brand Name: CERROPIAge Range Description: Adult/KidItem Weight: 1200 GramsItem Dimensions: 9.06 x 6.69 x 6.69 inchesSize: LargeMaterial Type: Nylon, Wood, SteelTheme: PhysicsOperation Mode: ManualEducational Objective: Logical ThinkingPower Source: ManualNumber of Players: 1 Shipping Free fast shipping Return Policy All items qualify for returns within 30 days of receipt.