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NEW Metal TTL Auto Focus Macro Extension Tube Ring Blue for Canon EOS EF EF-S UK

Features:
Support accurate TTL & Autofocus.
Built-in electric pins.
Compatible with all EF and EF-S Canon lenses.
Combined of 3 tubes with different length of: 13mm, 21mm, 31mm.
Made of high-quality Aluminum material that is stronger.
Upgraded circuitry to work better with digital SLRs cameras and SLR lenses.
Superior lock pin which can tighten the tube joint.
Perfect for macro shooting.
High quality and compact.

Specifications:
Color: Blue
Materials: Aluminum, PC, ABS
Compatibility: For all EF and EF-S Canon lenses
Macro tube size: 6.2 * 8cm / 2.4 * 3.1in (D * H)
Macro tube weight: 146g / 5.1oz
Package size: 9 * 7 * 7cm / 3.5 * 2.8 * 2.8in
Package weight: 185g / 6.5oz

Auto Extension Tube Distance Reading of Master Lens Image Magnification Ratio

Field Coverage (cm)

Distance From Lens Front to Subject (cm) Exposure Factor
13mm Inf. 0.24 10 * 15 21 1.5
0.5m 0.35 6.9 * 10.3 16 1.8
21mm Inf. 0.40 6 * 9 13 2.0
0.5m 0.51 4.7 * 7.0 14 2.3
31mm Inf. 0.72 3.3 * 5.0 7.7 3.0
0.5m 0.83 2.9 * 4.4 7.0 3.4
13+21mm Inf. 0.64 3.8 * 5.6 8.5 2.7
0.5m 0.75 3.2 * 4.8 7.5 3.1
13+31mm Inf. 0.96 2.5 * 3.7 6.0 3.9
0.5m 1.07 2.3 * 3.4 5.5 4.3
21+31mm Inf. 1.12 2.2 * 3.3 5.3 4.5
0.5m 1.23 2 * 3 4.9 5.0
13+21+31mm Inf. 1.34 1.8 * 2.7 4.5 5.6
0.5m 1.47 1.6 * 2.4 4.2 6.1

Package list:    【D928BL】
1 * Macro Extension Tube Set
1 * Bag
1 * User Manual