One really smart, compact USB rechargeable light that acts as either a front or a rear … it's a 2'Fer.

DETAILS 

COMPACT, LIGHT, AND BRIGHT 

The bright 60 lumen front and 20 lumen rear settings will let drivers know where you are.

SPECIFICATIONS 

Recharge Type: Micro-USB rechargeable — Charges via any standard USB port (charging cable included)

Brightness: 60 lumens front or 20 lumens rear

Sport: Cycling

Battery Type: Lithium Polymer

Country of Origin: China

Recharge Time: 3-hour recharge

Mounting Options: Mount to handlebars, seatposts, clip to racks, clothing, backpacks / No tools required

Product Weight: 18 grams

Run Time: High mode: front 1.5 hours at 60 lumens, rear 1.5 hours at 20 lumens / Flash mode: front 5 hours at 60 lumens, rear 5 hours at 20 lumens

Water Resistance: IP-65 submersible - Ingress protection rating or "IP Rating," is a techy way to describe the level of water- and dust-proofness of a product. This light meets the IP-65 Standard, which means it is totally protected against dust/grit and protected against low-pressure water jets from any direction.