Based on this product's specifications, here are some alternatives and similar models
Optical attenuator CBO SFA21BK11 — Singlemode LC Simplex 11 dB
Summary description:
Passive optical attenuator CBO SFA21BK11 for singlemode fibre networks with LC simplex connector and 11 dB attenuation. Designed to reduce signal power to match receiver sensitivity, it suits testing, link commissioning and protecting active components. Compact inline design for rack, patch panels or field use; plug-and-play installation without configuration.