This is a 35/35 size Euro cylinder, but it’s not reversible. One side, the one with the keyhole, goes on the outside. This side has the anti-snap protection. Open your door and measure from the centre M5 screw on the side of the door, to the edge of your existing cylinder on the inside of your door. This is the 'B' measurement. For example, this might be 40mm. Be careful to note the external measurement as TS007 3-star cylinders are non-reversible, so you have to get the specific internal and external measurements.

Visually, the Platinum 3 Star Cylinder deters intruders with its clearly identified 3 Star Kitemark logo on the face of the cylinder. It has a flat, horizontal key way with reversible key. This double cylinder (key operated at both ends) is also available with convenience of a thumbturn on the inside. Features & BenefitsAn alternative specification to look out for is the TS007 BSI Kitemark, however, it is important to note that there is a star rating associated with this. It's important you choose the right size cylinder for your door, so it fits properly. To measure your cylinder: A Kitemark indicates the product has been tested by a 3rd party and hasn’t simply been approved to the standard by the manufacturer themselves A 3 Star Rating Protects Against Snapping Put these two measurements together to get the right size - your B measurement goes first e.g. 40/50.

Then, measure from the centre M5 screw to the edge of your existing cylinder on the outside of your door. This is the 'A' measurement. For example, this might be 50mm The new Yale 3 Star AS Platinum cylinder is independently tested by BSI to be awarded the British Kitemarked TS007:2014 3 star accreditation.The Era Fortress Euro cylinder barrel has three certifications: TS007 3-star, Sold Secure Diamond and Secured by Design. You can also take out the current cylinder and measure the distance from the centre of the hole to the outer and inner edges of the cylinder. These are a doddle to fit when you know how. I’d recommend doing it yourself as there’s no technical knowledge required. Just watch a YouTube video. It’s a simple screw and replacement of the barrel: job done.