I am selling this item because I mistakenly purchased the wrong size stem bolt. It has been opened but is new and unused. This product is for M5 size stem bolts. ~~~~~~~~~ Product Details ~~~~~~~~~~~~ Material: AL6061 Aluminum Alloy Weight: Basic Type: Approx. 39g, Adjustable Type: Approx. 45g Compatible Models: Garmin/Bryton/Wahoo/GPS/igpsport/Bike Lights/GoPro Cameras Features: Lightweight/Durable/Multi-functional/Vibration Dampening/Anti-Drop/Easy Installation About this product 【High-Quality Material】The ROCKBROS cycling computer mount is made of AL6061 aluminum alloy, which is lightweight yet durable. It weighs only 39g (basic type) / 45g (adjustable type). The included Garmin/Bryton/Wahoo bases are made of PA resin, which is highly resistant to wear and impact, so you can use them with confidence. 【Compatible Models】Can be installed on cycle computers (Garmin/Bryton/IGS/Wahoo/XOSS), GPS, bike lights, GoPro cameras, etc., and two can be installed simultaneously. Perfect for cycling and outdoor activities. (Please note that this may not be compatible with all models, so please check before purchasing.) 【Comfortable Viewing Angle】Can be installed in front of the stem, making it easier to see. Positioning is possible in an easy-to-see and easy-to-operate position. In addition, it is easy to see at an angle parallel to the stem, and it does not interfere with cycling. The adjustable type allows you to freely control the angle of the cycling computer. 【Easy Installation】Package contents: Bracket body (Garmin base included), 1 Bryton base, 1 Wahoo base, 1 2mm/4mm hex wrench, 2 spacers, 2 8*15mm spacers, 2 M5*45mm internal hex socket head screws. (Note: Applicable stem distance within 4 cm, please measure the appropriate distance of your car before purchasing.)