Description: Material: Adopt of aluminum alloy materials and made by machining, a precise balance of glass and resin with no air pockets, durable and sturdy to use. Function: Used for removing air bubbles from lamination, leveling and compaction of resin coating to drive bubbles, and you just never know when you can use a random tool for something other than the designed purpose to save the day. These aluminum rollers set the industry standard for durability and ease of cleaning. Plastic handles are solvent-resistant for easy cleaning. Application: Widely used in the production of glass fiber reinforced plastic, and the inner surface of the bubble roller puncture. 4pcs fiberglass roller set:1x 5" larger diameter, 1x larger diameter which has deeper grooves for thicker laminate roll-out, 1x smaller diameter relieves more numerous small bubbles on a thinner laminate, 1x corner roller for air in crucial filets and corners. Specification: Size: 50x13mm / 1.96x0.51inch 20x75mm / 0.78inchx2.95inch 10x50mm / 0.39x1.96inch 12.5x125mm / 0.49x4.92inch Package Includes: 4 Pieces Fiberglass Resin Laminating Bubble Roller Kit Note: Please allow 1-3mm measuring deviation due to manual measurement. Due to the different monitor and light effect,the actual color of the item might be slightly different from the color showed on the pictures.Thank you!