A no-fuss secondary lock for lower-risk situations, the ABUS Tresor 6512C Combo Chain Lock is a super flexible coil cable with a four-digit combination you set yourself — handy for sharing with a group or just skipping the whole "where did I put my key" situation. The plastic coating keeps your bike's paint scratch-free, the 2-component number reels stay legible over time, and the whole thing coils up compact enough to toss in a bag or mount to your frame. Best used paired with a heavier lock for anything beyond a quick stop.