Name: Reciprocating straight line machine Length 221mm Width 38mm Thickness 48mm Weight: 46.7 grams Function: Through the power supply, speed reducer rotation, rocker arm and linkage linkage and long nail linear reciprocating motion, linear machine to achieve its own work effect. Hign-concerned Chemical:None Purchase Notes: 1. This productis a science experiment kit, non-toy! 2. This product is suitable for use in educational institutions, non-educational institutions to buy a detailed understanding of the use of this product scenarios, students in the use of this product must have a teacher or guardian to guide the use of. 3. This product is not a terminal retail products, end-customer purchase, the product seller must affirm to -customer of the product for science experiment materials, teachers or guardians need to guide the use of the product! (Parts only, powered by 2 AA batteries, no batteries included) Color: As shown Material: Wood + Metal + Plastic Package Contents: 1 * Telescopic mechanism electric model set Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.